C program to reverse a string using recursion

Write a C program to find reverse of a string using recursion.

  #include <stdio.h>
  #include <string.h>

  /* finds the reverse of the given input string using recursion */
  void reverseString(char *string, char *res) {
        if (*string) {
                reverseString(string + 1, res - 1);
                *res = *string;
        }
        return;
  }

  int main() {
        char string[256], output[256];

        /* get the input string from the user */
        printf("Enter your input string:");
        fgets(string, 256, stdin);
        string[strlen(string) - 1] = '\0';

        /* fill output with null */
        memset(output, '\0', sizeof(output));

        /* reverse the given input string and store the result in output */
        reverseString(string, (output + strlen(string) - 1));
        printf("Reverse of %s is %s\n", string, output);

        return 0;
  }

  Output:

  jp@jp-VirtualBox:~/$ ./a.out
  Enter your input string:helloworld
  Reverse of helloworld is dlrowolleh