HDOJ-1000 A + B Problem

A + B Problem Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 779856    Accepted Submission(s): 238542   Problem Description 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   Sample Output 2   Author HDOJ   Recommend We have carefully selected several similar problems for you:  1001 1089 1002 1090 1091

我居然提交了两次都wrong answer

//这是一个wrong answer
#include <iostream>
using namespace std;

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

结果居然是要加while判定两个整数有没有输入

#include <iostream>
using namespace std;

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