#include<iostream> 
using namespace std;
int main()
{
    int a, b;
    while(cin>> a >> b)
    cout << a + b << endl;
    return 0;
}

1 2
3

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main(){
  int n;
  cin >> n;
  int a[n];
  for(int i = 1; i <= n; i++){
    cin >> a[i - 1];
  }
  for(int i = 1; i <= n; i++){
    cout << *(a+i-1) << ",";
  }
  cout << endl;
  return 0;
} 

9
1 2 3 4 5 6 7 8 9
1,2,3,4,5,6,7,8,9,

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main(){
  vector<int> v;
  int num;
  for(int i = 0; ; i++){
    cin >> num;
    v.push_back(num);
    if(getchar() == '\n'){
      break;
    }
  }
  cout << "v.size()：" << v.size() << endl; 
  return 0;
} 

1 2 3 4 5 6
v.size()：6

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main(){
  int m, n;  //指定矩阵行列数 
  cin >> m >> n;
  int mat[m][n];
  for(int i = 0; i < m; i++){
    for(int j = 0; j < n; j++){
      cin >> mat[i][j];
    }
    getchar();   //吞掉换行符 
  }
  cout << "输出：" << endl;
  for(int i = 0; i < m; i++){
    for(int j = 0; j < n; j++){
      cout << mat[i][j] << ",";
    }
    cout << endl; 
  }
  return 0;
} 

2
2
1 2 3 4 5
输出：
1,2,
3,4,

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main(){
  string s;
  getline(cin, s);
  cout << "s：" << s << endl; 
  return 0;
} 

123 aaa
s：123 aaa

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main(){
  char s[256];
  cin.getline(s, 256, '\n');
  cout << "s：" << s << endl;
  return 0;
} 

111 aaa
s：111 aaa