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Рядки C++

У C++ рядок є об’єктом std::string клас, який представляє послідовність символів. Ми можемо виконувати багато операцій над рядками, таких як конкатенація, порівняння, перетворення тощо.


Приклад рядка C++

Давайте розглянемо простий приклад рядка C++.

 #include using namespace std; int main( ) { string s1 = &apos;Hello&apos;; char ch[] = { &apos;C&apos;, &apos;+&apos;, &apos;+&apos;}; string s2 = string(ch); cout&lt;<s1<<endl; cout<<s2<<endl; } < pre> <p>Output:</p> <pre> Hello C++ </pre> <hr> <h2>C++ String Compare Example</h2> <p>Let&apos;s see the simple example of string comparison using strcmp() function.</p> <pre> #include #include using namespace std; int main () { char key[] = &apos;mango&apos;; char buffer[50]; do { cout&lt;&gt;buffer; } while (strcmp (key,buffer) != 0); cout&lt;<'answer is correct!!'<<endl; return 0; } < pre> <p>Output:</p> <pre> What is my favourite fruit? apple What is my favourite fruit? banana What is my favourite fruit? mango Answer is correct!! </pre> <hr> <h2>C++ String Concat Example</h2> <p>Let&apos;s see the simple example of string concatenation using strcat() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); cout &lt;&lt; &apos;Enter the buffer string: &apos;; cin.getline(buffer, 25); strcat(key, buffer); cout &lt;&lt; &apos;Key = &apos; &lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos; &lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let&apos;s see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); strcpy(buffer, key); cout &lt;&lt; &apos;Key = &apos;&lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos;&lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let&apos;s see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = &apos;Welcome to C++ Programming&apos;; cout &lt;&lt; &apos;Length of String = &apos; &lt;&lt; strlen(ary)&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string&amp; str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string&amp; str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string&amp; replace(int pos,int len,string&amp; str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string&amp; append(const string&amp; str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char&amp; at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string&amp; str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string&amp; str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string&amp; str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string&amp; str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string&amp; str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string&amp; insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string&amp; assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string&amp; str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char&amp; back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string&amp; erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char&amp; front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&amp;&#xFFFD; operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string&amp; operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;></pre></'answer></pre></s1<<endl;>

Приклад порівняння рядків C++

Розглянемо простий приклад порівняння рядків за допомогою функції strcmp().

 #include #include using namespace std; int main () { char key[] = &apos;mango&apos;; char buffer[50]; do { cout&lt;&gt;buffer; } while (strcmp (key,buffer) != 0); cout&lt;<\'answer is correct!!\'<<endl; return 0; } < pre> <p>Output:</p> <pre> What is my favourite fruit? apple What is my favourite fruit? banana What is my favourite fruit? mango Answer is correct!! </pre> <hr> <h2>C++ String Concat Example</h2> <p>Let&apos;s see the simple example of string concatenation using strcat() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); cout &lt;&lt; &apos;Enter the buffer string: &apos;; cin.getline(buffer, 25); strcat(key, buffer); cout &lt;&lt; &apos;Key = &apos; &lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos; &lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let&apos;s see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); strcpy(buffer, key); cout &lt;&lt; &apos;Key = &apos;&lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos;&lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let&apos;s see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = &apos;Welcome to C++ Programming&apos;; cout &lt;&lt; &apos;Length of String = &apos; &lt;&lt; strlen(ary)&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string&amp; str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string&amp; str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string&amp; replace(int pos,int len,string&amp; str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string&amp; append(const string&amp; str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char&amp; at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string&amp; str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string&amp; str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string&amp; str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string&amp; str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string&amp; str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string&amp; insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string&amp; assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string&amp; str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char&amp; back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string&amp; erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char&amp; front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&amp;&#xFFFD; operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string&amp; operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;></pre></\'answer>

Приклад C++ String Concat

Розглянемо простий приклад конкатенації рядків за допомогою функції strcat().

бінарний пошук
 #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); cout &lt;&lt; &apos;Enter the buffer string: &apos;; cin.getline(buffer, 25); strcat(key, buffer); cout &lt;&lt; &apos;Key = &apos; &lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos; &lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let&apos;s see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); strcpy(buffer, key); cout &lt;&lt; &apos;Key = &apos;&lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos;&lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let&apos;s see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = &apos;Welcome to C++ Programming&apos;; cout &lt;&lt; &apos;Length of String = &apos; &lt;&lt; strlen(ary)&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string&amp; str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string&amp; str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string&amp; replace(int pos,int len,string&amp; str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string&amp; append(const string&amp; str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char&amp; at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string&amp; str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string&amp; str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string&amp; str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string&amp; str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string&amp; str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string&amp; insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string&amp; assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string&amp; str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char&amp; back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string&amp; erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char&amp; front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&amp;&#xFFFD; operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string&amp; operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;>

Приклад копіювання рядка C++

Давайте розглянемо простий приклад копіювання рядка за допомогою функції strcpy().

 #include #include using namespace std; int main() { char key[25], buffer[25]; cout &lt;&lt; &apos;Enter the key string: &apos;; cin.getline(key, 25); strcpy(buffer, key); cout &lt;&lt; &apos;Key = &apos;&lt;&lt; key &lt;&lt; endl; cout &lt;&lt; &apos;Buffer = &apos;&lt;&lt; buffer&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let&apos;s see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = &apos;Welcome to C++ Programming&apos;; cout &lt;&lt; &apos;Length of String = &apos; &lt;&lt; strlen(ary)&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string&amp; str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string&amp; str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string&amp; replace(int pos,int len,string&amp; str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string&amp; append(const string&amp; str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char&amp; at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string&amp; str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string&amp; str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string&amp; str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string&amp; str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string&amp; str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string&amp; insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string&amp; assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string&amp; str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char&amp; back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string&amp; erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char&amp; front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&amp;&#xFFFD; operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string&amp; operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;>

Приклад довжини рядка C++

Розглянемо простий приклад визначення довжини рядка за допомогою функції strlen().

 #include #include using namespace std; int main() { char ary[] = &apos;Welcome to C++ Programming&apos;; cout &lt;&lt; &apos;Length of String = &apos; &lt;&lt; strlen(ary)&lt;<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string&amp; str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string&amp; str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string&amp; replace(int pos,int len,string&amp; str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string&amp; append(const string&amp; str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char&amp; at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string&amp; str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string&amp; str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string&amp; str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string&amp; str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string&amp; str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string&amp; insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string&amp; assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string&amp; str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char&amp; back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string&amp; erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char&amp; front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&amp;&#xFFFD; operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string&amp; operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;>

Рядкові функції C++

функція опис
int compare(const string& str) Він використовується для порівняння двох рядкових об’єктів.
int length() Він використовується для визначення довжини струни.
void swap(string&str) Він використовується для обміну значеннями двох рядкових об’єктів.
string substr(int pos,int n) Він створює новий рядковий об’єкт із n символів.
int size() Він повертає довжину рядка в байтах.
void resize(int n) Використовується для зміни розміру рядка до n символів.
string& replace(int pos,int len,string& str) Він замінює частину рядка, яка починається в позиції символу pos і охоплює len символів.
string& append(const string& str) Він додає нові символи в кінці іншого рядкового об’єкта.
char& at(int pos) Він використовується для доступу до окремого символу у вказаній позиції.
int find(string& str,int pos,int n) Він використовується для пошуку рядка, зазначеного в параметрі.
int find_first_of(string& str,int pos,int n) Він використовується для пошуку першого входження зазначеної послідовності.
int find_first_not_of(string& str,int pos,int n) Він використовується для пошуку в рядку першого символу, який не збігається з жодним із символів, указаних у рядку.
int find_last_of(string& str,int pos,int n) Використовується для пошуку в рядку останнього символу вказаної послідовності.
int find_last_not_of(string& str,int pos) Він шукає останній символ, який не відповідає вказаній послідовності.
string& insert() Він вставляє новий символ перед символом, позначеним позицією pos.
int max_size() Знаходить максимальну довжину рядка.
void push_back(char ch) Він додає новий символ ch в кінці рядка.
void pop_back() Він видаляє останній символ рядка.
string& assign() Він присвоює рядку нове значення.
int copy(string&str) Він копіює вміст рядка в інший.
char& назад() Він повертає посилання на останній символ.
Ітератор begin() Він повертає посилання на перший символ.
int capacity() Він повертає виділений простір для рядка.
const_iterator cbegin() Він вказує на перший елемент рядка.
const_iterator cend() Він вказує на останній елемент рядка.
void clear() Він видаляє всі елементи з рядка.
const_reverse_iterator crbegin() Він вказує на останній символ рядка.
const_char* дані() Він копіює символи рядка в масив.
bool порожній() Він перевіряє, порожній рядок чи ні.
string& erase() Він видаляє вказані символи.
char& front() Він повертає посилання на перший символ.
рядок&� оператор+=() Він додає новий символ у кінець рядка.
рядок& оператор=() Він присвоює рядку нове значення.
char operator[](pos) Він отримує символ у вказаній позиції поз.
int rfind() Він шукає останнє входження рядка.
ітератор end() Він посилається на останній символ рядка.
reverse_iterator rend() Він вказує на перший символ рядка.
void shrink_to_fit() Це зменшує ємність і робить її рівною розміру струни.
char* c_str() Він повертає вказівник на масив, який містить послідовність символів із закінченням нульовим значенням.
const_reverse_iterator crend() Він посилається на перший символ рядка.
reverse_iterator rbegin() Він посилається на останній символ рядка.
резерв пустоти (inr len) Він вимагає зміни потужності.
allocator_type get_allocator(); Він повертає виділений об’єкт, пов’язаний із рядком.