#include<bits/stdc++.h>
using namespace std;
int gys(int a,int b){
	int x;
	while(a%b!=0)
	{
		x=a%b;
		a=b;
		b=x;
	}
	return b;
}
int a1,b1,a2,b2;
char s;
int main(){
	scanf("%d/%d",a1,b1);
	while(scanf("%c%d/%d",&s,&a2,&b2)==3)
	{
		a1=a1*b2+a2*b1;
		b1=b1*b2;
	}
	int t=gys(a1,b1);
	if(b1/t==1)
	cout<<a1/t;
	else
	cout<<a1/t<<"/"<<b1/t;
	return 0;
}