#include <algorithm>
#include <cstdio>
#include <cstring>
#include <iostream>
#define endl '\n'
#define int long long

using namespace std;

typedef pair<int, int> PII;
#define x first
#define y second

int gcd(int a, int b)
{
    if (b == 0)
    {
        return a;
    }
    else
    {
        return gcd(b, a % b);
    }
}

PII gcd(int a, int b, int c, int d)
{
    int up, down;
    up = gcd(a, c);
    down = b * d / gcd(b, d);
    return make_pair(up, down);
}

// 分数的最大公因数等于分子的最大公因数/分母的最小公倍数,两个数的最小公倍数等于其乘积除以最大公因数;

signed main(void)
{
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    PII t = gcd(a, b, c, d);
    cout << t.x << '/' << t.y << endl;
    return 0;
}