關於時間轉換可以參考以下博客：

https://www.jianshu.com/p/80de04b41c31

https://www.cnblogs.com/qicosmos/p/3642712.html

https://blog.csdn.net/wizardtoh/article/details/81738682

https://blog.csdn.net/hou8389846/article/details/77962343

get_time put_time相關

https://blog.csdn.net/wangjieest/article/details/7761051

https://www.yiibai.com/cpp_standard_library/cpp_get_time.html

time_point 相關

https://www.xuebuyuan.com/716692.html?mobile=1

hdu 6491

時間間隔

Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 153 Accepted Submission(s): 96

T (1≤T≤100000) 表示數據組數。

對於每組數據，一行一個字符串表示時間。
時間格式為：YYYY-MM-DD HH:MM:SS，分別表示年、月、日、時，分、秒。

輸入的時間保證都在2019年1月1日以後（包含當天）。

#include<bits/stdc++.h>
using
 
 namespace std;

int main()
{
    string s;
    stringstream ss;
    s = "2050-01-01 00:00:00";
    ss << s;
    tm beg ;
    ss >> get_time(&beg,"%Y-%m-%d");
    ss >> get_time(&beg,"%H:%M:%S");
    auto next_time = chrono::system_clock::from_time_t(time_t(mktime(&beg)));
    int n;
    cin>>n;
    while(n--)
    {
        tm ed;
        cin >> get_time(&ed,"%Y-%m-%d");
        cin >> get_time(&ed,"%H:%M:%S");
        auto from_time = chrono::system_clock::from_time_t(time_t(mktime(&ed)));
        auto diff = next_time - from_time ;
        cout<<abs(chrono::duration_cast<chrono::seconds>(diff).count())%100<<endl;
    }
    return 0;
}

c++ 時間相關的類型