C Program To Check String Is Palindrome Or Not

#include <stdio.h>
#include <string.h>
int main()
{
  	char str[100];
  	int i, len, flag;
  	flag = 0;
  	printf("\n Please Enter any String :  ");
  	gets(str);
  	len = strlen(str);
  	for(i = 0; i < len; i++)
	{
		if(str[i] != str[len - i - 1])
		{
			flag = 1;
			break;
		}
	}
	if(flag == 0)
	{
		printf("\n %s is a Palindrome String", str);
	}
	else
	{
		printf("\n %s is Not a Palindrome String", str);
	}
  	return 0;
}