std::memchr in C++
C++ offers various standard template library functions to be used. One of them is memchr() function which is used to search for the first occurrence of a character in a specified number of characters.
memchr() is defined inside <cstring> header file.
Syntax of memchr()
const void* memchr( const void* ptr, int ch, std::size_t count );
Parameters
- ptr: Pointer to the object where the search will be performed.
- ch: Character to search for.
- count: Number of characters to be searched for.
Return Value
- If the character is found, the memchr() function returns a pointer to the location of the character otherwise,
- If the character is not found, it returns the NULL Pointer.
Examples of memchr()
Example 1
The following C++ program illustrates the use of memchr() function to search for a character in a string.
C++
Output
s is present in first 13 characters of "This is a sample"
Example 2
The following C++ program illustrates the use of memchr() function to search for a character in an array of characters.
C++
// CPP program to illustrate memchr() #include <cstring> #include <iostream> using namespace std; int main() { char arr[] = { 'b' , 'a' , 'd' , 'e' , 'f' , 'A' , 'g' }; // checking the presence of 'g' char * pc = ( char *) memchr (arr, 'g' , sizeof arr); if (pc != NULL) cout << "search character found\n" ; else cout << "search character not found\n" ; } |
Output
search character found
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