C++ 已知两个时间（年月日）求日期差

求日期差

例如,我想算一下现在(2016.11.21)到明年高考(2017.6.7)还有多少天

#include<iostream>    
#include <ctime>  

using namespace std;  

int main() {  
    struct tm t1 = { 0 };  
    struct tm t2 = { 0 };  
    double seconds;  

    t1.tm_year = 2016 - 1900; t1.tm_mon = 10; t1.tm_mday = 21;//现在时间2016,11,21  
    t2.tm_year = 2017 - 1900; t2.tm_mon = 5; t2.tm_mday = 7;//高考时间2017,6,7  

    seconds = difftime(mktime(&t2), mktime(&t1));//转换结构体为time_t,利用difftime,计算时间差  

    cout << seconds / 86400 << endl;//最后输出时间,因为一天有86400秒(60*60*24)  
    system("pause");  
    return 0;  
}  

转载自：https://blog.csdn.net/l773575310/article/details/53258230