#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll gcd(ll p,ll q){
	return q?gcd(q,p%q):p;
}
int main(){
	ll t1,t2,t3;
	ll temp,m;
	cin>>t1>>t2>>t3;
	m=__gcd((t3-t1)*t2,(t3-t2)*t1);
	temp=__gcd(t1*t2*t3,m);
	printf("%ld/%ld",t1*t2*t3/temp,m/temp);
	return 0;
}