#include <bits/stdc++.h>
using namespace std;
long long gcd(long long x,long long y){
	return y?gcd(y,x%y):x;
}
int main(){
	long long xz,xm,yz,ym;
	scanf("%lld/%lld",&xz,&xm);
	while(scanf("%lld/%lld",&yz,&ym)!=EOF){
		xz=xz*ym+yz*xm;
		xm*=ym;
		long long m=gcd(xz,xm);
		xz/=m;
		xm/=m;
	}
	if(xm<0){
		xz=-xz;
		xm=-xm;
	}
	if(xm==1){
		printf("%lld\n",xz);
	}
	else{
		printf("%lld/%lld\n",xz,xm);
	} 
	return 0;
}