#include<iostream>
#include<cstdio>
#include<vector>
#include<queue>
#include<map>
#include<string>
#include<algorithm>
#include<functional>
using namespace std;
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#define INF 1<<30
#define MP make_pair
#define mp make_pair
#define pb push_back
#define PB push_back
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define ll long long
#define ull unsigned long long

ll GCM(ll a, ll b){
	if(b>a) swap(b,a);
	if(a%b==0) return b;
	return GCM(b,a%b);
}
ll LCM(ll a,ll b){
	if(a<b) swap(a,b);
	if(b==1) return a;
	return a*(b/GCM(a,b));
}

int main(){
	ll t1,t2,t3;cin>>t1>>t2>>t3;
	ll d = 2*t1*t2*t3;
	ll n1=2*(t3-t1)*t2;
	ll n2=2*(t2-t1)*t3;
	ll n3=2*(t3+t1)*t2;
	ll n4=2*(t2+t1)*t3;
	ll l[4]={GCM(n1,n2) ,GCM(n1,n4) ,GCM(n3,n2) ,GCM(n3,n4)};
	sort(l,l+4);reverse(l,l+4);
	ll a=d;
	ll b=l[0];
	cout<<a/GCM(a,b)<<"/"<<b/GCM(a,b)<<endl;
}