#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

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

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

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    ll L, T1, T2, T3;
    while(cin >> T1 >> T2 >> T3){
        L = lcm(T1, lcm(T2, T3));
        ll x, y, z;
        x = L / T1;
        y = L / T2;
        z = L / T3;
        for(int m = (int)x; m >= 1; --m){
            ll xm = x%m, ym = y%m, zm = z%m;
            if(xm == ym&&ym == zm&&zm == xm){
                ll g = gcd(L, m);
                ll a = L / g;
                ll b = m / g;
                cout << a << '/' << b << endl;
                break;
            }
        }
    }
}