015.运算符-算术运算符-加减乘除

#include <iostream>
using namespace std;
int main()
{
     //加减乘除

    int a = 10;
    int b = 3;

    cout << a + b << endl;      //加
    cout << a - b << endl;      //减
    cout << a * b << endl;      //乘
    cout << a / b << endl;      //除，两个整数相除，依然是整数，除去小数部分


    int a2 = 20;
    int b2 = 10;
    cout << a2/b2 << endl;     


    int a3 = 10;
    int b3 = 0;
    //cout << a3 / b3 << endl;    除数不能为0，运行是出错


    double d1 = 0.5;
    double d2 = 0.25;
    cout << d1 / d2 << endl;   //运算结果可以是小数；
    
    system("pause");
    return 0;
}