#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cmath>
#include <iomanip>
#include <map>
using namespace std;
typedef long long LL;

LL gcd(LL a, LL b){
    if(a > b) swap(a, b);
    if(a == 0) return b;
    return gcd(b % a, a);
}

LL lcm(LL a, LL b){
    return a * b / gcd(a, b);
}

int main(){
    LL t1, t2, t3;
    cin >> t1 >> t2 >> t3;
    LL m = lcm(t1, lcm(t2, t3));
    LL c1 = m / t1;
    LL c2 = m / t2;
    LL c3 = m / t3;
    LL d = 1;
    for(LL i = 1; i <= 20000; i++){
        LL r1 = c1 - c1 / i * i;
        LL r2 = c2 - c2 / i * i;
        LL r3 = c3 - c3 / i * i;
        if((r1 == r2 || (r1*2 <= i && r1 == i-r2) || (i-r1 == r2 && r2*2 <= i))
            && (r1 == r3 || (r1*2 <= i && r1 == i-r3) || (i-r1 == r3 && r3*2 <= i))){
            d = i;
        }
    }
    cout << m << "/" << d << endl;
    return 0;
}