reversing a string in c code example

Example 1: reverse string efficient in cpp without using function

#include <iostream>
using namespace std;
int main()
{
    char str[] = "Reverseme";
    char reverse[50];
    int i=-1;
    int j=0;
         /*Count the length, until it each at the end of string.*/ 
          while(str[++i]!='\0');
           while(i>=0)
                    reverse[j++]=str[--i];
            reverse[j]='\0';
      cout<<"Reverse of  a string is"<< reverse;
      return 0;
}

Example 2: code to reverse a string

#include <stdio.h>
#include <string.h>
int main()
{
   char s[100];

   printf("Enter a string to reverse\n");
   gets(s);

   strrev(s);

   printf("Reverse of the string: %s\n", s);

   return 0;
}