# C++ 程序：计算两个时间段之间的差异

> 原文： [https://www.programiz.com/cpp-programming/examples/time-structure](https://www.programiz.com/cpp-programming/examples/time-structure)

要理解此示例，您应该了解以下 [C++ 编程](/cpp-programming "C++ tutorial")主题：

*   [C++ 结构](/cpp-programming/structure)
*   [C++ 结构和功能](/cpp-programming/structure-function)
*   [C++ 指向结构的指针](/cpp-programming/structure-pointer)

* * *

* * *

## 示例：程序与时间差异

```cpp
// Computes time difference of two time period
// Time periods are entered by the user

#include <iostream>
using namespace std;

struct TIME
{
  int seconds;
  int minutes;
  int hours;
};

void computeTimeDifference(struct TIME, struct TIME, struct TIME *);

int main()
{
    struct TIME t1, t2, difference;

    cout << "Enter start time." << endl;
    cout << "Enter hours, minutes and seconds respectively: ";
    cin >> t1.hours >> t1.minutes >> t1.seconds;

    cout << "Enter stop time." << endl;
    cout << "Enter hours, minutes and seconds respectively: ";
    cin >> t2.hours >> t2.minutes >> t2.seconds;

    computeTimeDifference(t1, t2, &difference);

    cout << endl << "TIME DIFFERENCE: " << t1.hours << ":" << t1.minutes << ":" << t1.seconds;
    cout << " - " << t2.hours << ":" << t2.minutes << ":" << t2.seconds;
    cout << " = " << difference.hours << ":" << difference.minutes << ":" << difference.seconds;
    return 0;
}
void computeTimeDifference(struct TIME t1, struct TIME t2, struct TIME *difference){

    if(t2.seconds > t1.seconds)
    {
        --t1.minutes;
        t1.seconds += 60;
    }

    difference->seconds = t1.seconds - t2.seconds;
    if(t2.minutes > t1.minutes)
    {
        --t1.hours;
        t1.minutes += 60;
    }
    difference->minutes = t1.minutes-t2.minutes;
    difference->hours = t1.hours-t2.hours;
} 
```

**输出**

```cpp
Enter hours, minutes and seconds respectively: 11
33
52
Enter stop time.
Enter hours, minutes and seconds respectively: 8
12
15

TIME DIFFERENCE: 11:33:52 - 8:12:15 = 3:21:37 
```

在该程序中，要求用户输入两个时间段，这两个时间段分别存储在结构变量`t1`和`t2`中。

然后，`computeTimeDifference()`函数计算时间段之间的时差，结果从`main()`函数显示在屏幕上，而不会返回（通过引用调用）。