1.C++入门

#include "iostream"
void print_add(int a,int b);
int int_add(int a,int b);
int main()
{
    using namespace std;
    cout<<"hello\r\n";
    print_add(1,2);
}
void print_add(int a,int b)
{
    using std::cout;
    cout<<"a+b="<<int_add(a,b);
}

int int_add(int a,int b)
{
    std::cout<<"a is "<<a<<"\r\nb is "<<b<<std::endl;
    return a+b;
}