#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int gcd(int a,int b){
  if(b!=0){
    return gcd(b,a%b);
  } else {
    return a;
  }
}
int lcm(int a,int b){
  return a*b/gcd(a,b);
}
int main(){
  int T1=0,T2=0,T3=0;cin>>T1>>T2>>T3;
  int x=lcm(T1,lcm(T2,T3));
  vector<int> v(3);
  v[0]=x/T1;
  v[1]=x/T2;
  v[2]=x/T3;
  sort(v.begin(),v.end());
  int a=v[1]-v[0];
  int b=v[2]-v[1];
  int y=gcd(a,b);
  cout<<x<<"/"<<y<<endl;
}