求两数和——
#include<iostream>
using namespace std;
int main()
{
int a,b,c;
cin>>a>>b;
c=a+b;
cout<<"sum="<<c<<endl;
return 0;
}

输出Hello World!——
//Hello World.cpp
#include<iostream>
using namespace std;
int main()
{
cout<<"Hello World!"<<endl;
return 0;
}

求两数之和——
//Sum.cpp
#include<iostream>
using namespace std;
int main()
{
int x,y,sum;
cout<<"Enter two numbers:"<<endl;
cin>>x;
cin>>y;
sum=x+y;
cout<<"The sum is:"<<sum<<endl;
return 0;
}

你上次叫我看的天書。