#include <bits/stdc++.h>
using namespace std;

typedef long long loong;

loong gcd(loong a,loong b){return a?gcd(b%a,a):b;}

loong T1,T2,T3;

int main(){
	cin >> T1 >> T2 >> T3;
	loong d=T1*T2*T3;
	loong n1a=(T3-T1)*T2;
	loong n1b=(T3+T1)*T2;
	loong n2a=(T3-T2)*T1;
	loong n2b=(T3+T2)*T1;
	loong naa=gcd(n1a,n2a);
	loong nab=gcd(n1a,n2b);
	loong nba=gcd(n1b,n2a);
	loong nbb=gcd(n1b,n2b);
	loong n=max(max(naa,nab),max(nba,nbb));
	loong g=gcd(n,d);
	cout << d/g << "/" << n/g << endl;
	return 0;
}