#include<iostream>
using namespace std;
    float a[5001];
    int t[5001];
    int v[2000001];
int main()
{
    int n;
    for (int i = 0; i < 2000001; i++)
    {
        v[i] = 1;//所有路灯标记为1，开的变偶数，关的奇数
    }
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        cin >> a[i] >> t[i];
    }
    for (int i = 0; i < n; i++)//执行操作
    {
        for (int q = 0; q <= i; q++)
        {
            v[int(a[i] * t[q])]++;
        }
    }
    for (int i = 0; i < 2000000; i++)
    {
        if (v[i] % 2 == 0)
        {
            cout << i+1;
        }
    }
    return 0;
}

感谢！！！