网易编程题——牛牛的闹钟

/*

问题描述：A时B分上课，牛牛到教室要X分钟，所以牛牛最晚什么时候起床。

思考：不用思考，简单题最晚当然是 上课时间-从宿舍到教室花费的时间

*/
#include<algorithm>
#include<cmath>
#include<iostream>
#include<vector>
using namespace std;
int main()
{

    int num;
    cin >> num;
    int hour, minute;
    vector<int> time_v;
    for (int i = 0; i < num; i++)
    {
        cin >> hour >> minute;
        time_v.push_back(hour * 60 + minute);
    }
    int spend_hour;
    cin >> spend_hour;
    int school_h, shool_m;
    cin >> school_h >> shool_m;
    sort(time_v.begin(), time_v.end());
    int time = school_h * 60 + shool_m - spend_hour;
    for (int i = 1; i < num; i++)
    {
        if (time - time_v[i - 1] >= 0 && time - time_v[i] < 0)
        {
            cout << time_v[i - 1] / 60 << " ";
            cout << time_v[i - 1] % 60;
        }
    }
    system("pause");
    return 0;
}

方法二：

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin >> n;
    set<int> aSet;
    for(int i = 0; i < n; ++i)
    {
        int h,m;
        cin >> h >> m;
        int temp = 60*h + m;
        aSet.insert(temp);
    }
    int x;
    cin >> x;
    int h,m;
    cin >> h >> m;
    int temp = 60*h + m - x;
    auto it = upper_bound(aSet.begin(),aSet.end(),temp);
    it--;
    temp = *(it);
    cout << temp/60 << " " << temp%60;