[c++]常用关键字cin,cout，endl的使用

#include <iostream>
using namespace std;






int main() 
{
    int a;
    char b;

    std:: cout << "please input :"<<std:: endl;
    cin >> a >> b;

    std::cout << "the out put:" << std::endl;
    cout << a << ' ' << b << '\n' << endl;

    return 0;
}

?黄色框：先输入10，[回车]/空格输入字符

?如果不用"using namespace std;",则需要在cout和endl 前面加上"std::"：

#include <iostream>
//using namespace std;






int main() 
{
    int a;
    char b;

    std:: cout << "please input :"<<std:: endl;
    std:: cin >> a >> b;

    std::cout << "the out put:" << std::endl;
    std::cout << a << ' ' << b << '\n'<<std:: endl; 

    return 0;
}

endl为换行的作用，