#include <bits/stdc++.h>   using namespace std;   int gcd(int a, int b) {     if (a % b == 0)       return b;     else       return gcd(b, a % b);   }   int a, b, c, d;   int main() {     scanf( %d %d %d %d , &a, &b, &c, &d);     int t, bo;     if (a * d >= c * b) {       t = b * c;       bo = d * a;     } else {       t = a * d;       bo = c * b;     }     t = bo - t;     int cc = gcd(t, bo);     printf( %d/%d n , t / cc, bo / cc);   }   