#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

#define RREP(i,s,e) for (i = s; i >= e; i--)
#define rrep(i,n) RREP(i,(int)(n)-1,0)
#define REP(i,s,e) for (i = s; i <= e; i++)
#define rep(i,n) REP(i,0,(int)(n)-1)
#define INF 100000000

typedef long long ll;

ll gcd(ll a, ll b) {
    return b == 0 ? a : gcd(b,a%b);
}

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

int main() {
    ll a, b, c;
    ll cm1, cm2, cm, dv1, dv2;
    cin >> a >> b >> c;
    cm1 = lcm(a,b);
    cm2 = lcm(b,c);
    dv1 = abs(cm1 / a - cm1 / b);
    dv2 = abs(cm2 / b - cm2 / c);
    cm = lcm(cm1,cm2);
    cout << cm << "/";
    cout << gcd(cm/cm1*dv1,cm/cm2*dv2) << endl;
    return 0;
}