C - AtCoDeerくんと選挙速報 / AtCoDeer and Election Report

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;
#define inf (0x3f3f3f3f)
typedef long long int LL;

#include <iostream>
#include <sstream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <string>

void work() {
    int n;
    cin >> n;
    LL ansx = 1, ansy = 1;
    for (int i = 1; i <= n; ++i) {
        LL a, b;
        cin >> a >> b;
        LL k1 = 1;
        if (a < ansx) {
//            k1 = max(k1, (LL)ceil(1.0 * ansx / a)); ceil有毒？
            k1 = ansx / a;
            if (ansx % a != 0) k1++;
        }
        if (b < ansy) {
//            k1 = max(k1, (LL)ceil(1.0 * ansy / b));
            LL t = ansy / b;
            if (ansy % b != 0) t++;
            k1 = max(k1, t);
        }
        ansx = a * k1;
        ansy = b * k1;
    }
    cout << ansx + ansy << endl;
}

int main() {
#ifdef local
    freopen("data.txt","r",stdin);
#endif
    work();
    return 0;
}