1 实验内容简述：

实验1.1—1.4:

（1）求和；

#include <iostream>
using namespace std;
int main()
{
    int a, b, sum;
    cout << "输入两个数" << endl;
    cin >> a >> b;
    sum = a + b;
    cout << "sum = " << sum << endl;
    return 0;
}

（2）华氏温度转摄氏温度；

#include <iostream>;
using namespace std;
int main()
{
    double f, c;
    cout << "输入华氏温度:"<<endl;
    cin >> f;
    c = 5 * ( f - 32) / 9;
    cout << "摄氏温度：" << c << endl;
    return 0;
}

（3）求圆面积；

#include <iostream>
using namespace std;
int main()
{
    double Pi = 3.1415926,r;
    cout << "输入半径：" << endl;
    cin >> r;
    cout << "面积为：" << r * r * Pi;
    return 0;
}

（4）求三角形的周长和面积。

#include <iostream>
#include <cmath>
using namespace std;
int main()
{
    double a, b, c, p;
    cout << "输入三角形的三边：" << endl;
    cin >> a >> b >> c;
    if ((a + b > c) && (a + c > b) && (b + c > a))
    {
        p = (a + b + c) / 2;
         cout << "周长为：" << a + b + c << endl;
         cout << "面积为：" << sqrt(p * (p - a) * (p - b) * (p - c));
    }
    return 0;
}

实验2.1—2.2：

(1) 判断是否为三角形；

#include <iostream>
using namespace std;
int main()
{
    float a, b, c;
    cout << "input a b c\n";
    cin >> a >> b >> c;
    if ((a + b <= c) || (a + c <= b) || (b + c <= a))
        cout << "Not Triangle\n";
    else
        cout << "Triangle\n";
    return 0;
}

(2) 闰年判断。

#include <iostream>
using namespace std;
int main()
{
    int year;
    cout << "输入年份：" << endl;
    cin >> year;
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))
        cout << "是闰年" << endl;
    else
        cout << "不是闰年" << endl;
    return 0;
}