#include <bits/stdc++.h>
using namespace std;
int gcd(int a, int b)
{
    if (b == 0)
        return a;
    return gcd(b, a % b);
}
int main()
{
    // p/q
    int p = 0, q = 1;
    // 输入每个分数，累加进去
    int a, b;
    char c;
    while (cin >> a >> c >> b)
    {
        // (p / q) + (a / b) = (pb + aq) / bq
        int pp = p * b + a * q;
        int qq = b * q;
        p = pp / gcd(pp, qq);
        q = qq / gcd(pp, qq);
    }
    if (q < 0)
        p *= -1, q *= -1;
    if (q == 1)
        cout << p;
    else
        cout << p << "/" << q << "\n";
    return 0;
}