#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=a;i<b;i++)
typedef long long ll;
typedef vector<int> vi;
typedef vector<string> vs;
typedef pair<int, int> pii;

int euclid(int a, int b)
{
	int temp;

	if (a < b) { temp = a; a = b; b = temp; }
	if (b < 1) return -1;

	if (a % b == 0) return b;
	return euclid(b, a % b);
}

int main()
{
	int t1, t2, t3;
	cin >> t1 >> t2 >> t3;

	int up = t2 * t3 * abs(t2 - t1);
	int down = abs(t3 - t2) * t1 * t2;

	int a = euclid(up, down);
	up /= a;
	down /= a;

	int m = down;

	up = t2 * t3 * m;
	down = abs(t3 - t2);

	a = euclid(up, down);
	up /= a;
	down /= a;

	cout << up << "/" << down << endl;
}