MIN MAX OF TWO NUMBERS

PROBLEM LINK
https://www.hackerrank.com/contests/y16csecs/challenges/y16-min-max-of-two-numbers

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

int main() {

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    long int a,b;
    scanf("%ld %ld",&a,&b);
    if(a==b)
    {
        printf("-1");
    }
    else
    {
     
         if(a<b)
        {
            printf("%ld %ld",a,b);
        }
        else
        {
            printf("%ld %ld",b,a);
        }
    }
    return 0;
}