#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define each(a, b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
#define pb push_back
#define show(x) cout <<#x<<" = "<<(x)<<endl
#define spair(p) cout <<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout <<" "<<kbrni;cout<<endl

using namespace std;

typedef pair<int,int>P;

const int MAX_N = 100005;

ll gcd(ll a,ll b)
{
    if(a%b == 0){
        return b;
    }else{
        return gcd(b,a%b);
    }
}

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int t1,t2,t3;
    cin >> t1 >> t2 >> t3;
    vector<int> v1={t2+t1,t2-t1};
    vector<int> v2={t3+t2,t3-t2};
    ll bo = 0;
    rep(i,2){
        rep(j,2){
            bo = max(bo,gcd(v1[i],v2[j]));
        }
    }
    ll num1 = gcd(t1+t2,t1*t2);
    ll a1 = (t1+t2)/num1;
    ll a2 = (t1*t2)/num1;
    ll num2 = gcd(t1+t3,t1*t3);
    ll a3 = (t1+t3)/num2;
    ll a4 = (t1*t3)/num2;
    ll si = a2*a4 / gcd(a2,a4);
    ll hoge = gcd(si,bo);
    cout << si/hoge << "/" << bo/hoge << endl;
    return 0;
}