#include<cmath>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define int long long
int m;
int a,b,c,d;
signed main()
{
    scanf("%lld/%lld",&a,&b);
    while(scanf("%lld/%lld",&c,&d)!=EOF)
    {
       	m=__gcd(b,d);
        a*=d/m;
        c*=b/m;
        a+=c;
        b*=d/m;
        m=__gcd(a,b);
        a/=m;
        b/=m;
    }
    if(b<0)
    {
        a=-a;
        b=-b;
    }
    if(b==1)
        printf("%lld\n",a);
    else
        printf("%lld/%lld\n",a,b);
    return 0;
}

为啥编译错误