poj 01

第一次做poj…
纯小白，记录一下规则
Q: Where are the input and the output?

A: Your program shall always read input from stdin (Standard Input) and write output to stdout (Standard Output). For example, you can use ‘scanf’ in C or ‘cin’ in C++ to read from stdin, and use ‘printf’ in C or ‘cout’ in C++ to write to stdout.

You shall not output any extra data to standard output other than that required by the problem, otherwise you will get a “Wrong Answer”.

User programs are not allowed to open and read from/write to files. You will get a “Runtime Error” or a “Wrong Answer”if you try to do so.

Here is a sample solution to problem 1000 using C++/G++:

#include <iostream>

using namespace std;

int main()
{
        int a,b;
        cin >> a >> b;
        cout << a+b << endl;
        return 0;

}
It's important that the return type of main() must be int when you use G++/GCC,or you may get compile error. 

Here is a sample solution to problem 1000 using C/GCC: 
    #include <stdio.h>

    int main()
    {
            int a,b;
            scanf("%d %d",&a, &b);
            printf("%dn",a+b);
            return 0;

    }

read from stdin and output from stdout