C program to print the length of a String using %n format specifier

Given string str. The task is to find the length of the string using %n format specifier


Input: Geeks For Geeks
Output: 15

Input: Geeks
Output: 5


To find the length of string, we use special format specifier “%n” in printf function. In C printf(), %n is a special format specifier which instead of printing something causes printf() to load the variable pointed by the corresponding argument with a value equal to the number of characters that have been printed by printf() before the occurrence of %n.

Below is the implementation of the above approach:





// C program to print
// the length of a String
// using %n format specifier
#include <stdio.h>
// Driver code
int main()
    char str[100] = "Geeks for Geeks";
    int len = 0;
    printf("%s%n", str, &len);
    printf(" = %d", len);
    return 0;



Geeks for Geeks = 15

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