由于ACM题目的输入输出数据不定，格式多种多样，且要求严格，因此，如何处理题目的输入与输出至关重要。
（一）第一类输入：输入不说明有多少个Input Block，以EOF为结束标志。
Example1:
Calculate A + B .
Input：Each line will contain two integers A and B . Process to end of file.
Output：For each case, output A + B in one line.
Sample Input
1 1
2 2
Sample Output
2
4
C语言代码
#include < stdio.h >
int main()
{
int a,b;
scanf("%d %d",&a, &b);
printf("%d\n",a+b);
return 0;
}
C++语言代码
#include < iostream >
using namespace std;
int main()
{
int a,b;
cin >> a >> b;
cout << a+b << endl;
return 0;
}
（二）第二类输入：题目告诉有N个Input Block,下面接着是N个Input Block。
Example2:
Problem Description
Your task is to Calculate a + b.
Input:
Input contains an integer N in the first line, and then N lines follow. Each line consists of a pair of integers a and b, separated by a space, one pair of integers per line.
Output:
For each pair of input integers a and b you should output the sum of a and b in one line, and with one line of output for each line in input.
Sample Input:
2
1 5
10 20
Sample Output:
6
30
