C Program to reverse a string without using library function


In this program, You will learn how to reverse a string without using library function in c.


abcd => dcba

Xiith => htiiX


Example: How to reverse a string without using library function in c

Run it Now
#include<stdio.h>

int main() {

   char str[100], temp;
   int len = 0, i = 0;

   printf("Enter a String :");
   fgets(str, 100, stdin);

   while (str[len] != '\0') {
       len++;
   }
   len = len - 1;
   while (i < len) {
       temp = str[i];
       str[i] = str[len];
       str[len] = temp;
       len--;
       i++;
   }
   printf("\nAfter Reverse :%s", str);

   return 0;
}

Output:

Enter a String :JOHN SMITH
After Reverse :HTIMS NHOJ