#include <stdio.h>


int main()
{
   char string1[20], string2[20];

   printf("Primeira string:\n");
   gets(string1);

   printf("Segunda string:\n");
   gets(string2);

   if (comparar_strings(string1, string2) == 0)
      printf("Sao iguais!\n");
   else
      printf("Sao diferentes!\n");

   return 0;
}

int comparar_strings(char string1[], char string2[]){
   int c = 0;

   while (string1[c] == string2[c]) {
      if (string1[c] == '\0' || string2[c] == '\0')
         break;
      c++;
   }

   if (string1[c] == '\0' && string2[c] == '\0')
      return 0;
   else
      return -1;
}