[c++] vector 배열

vector<int> map[10001];

int main()
{
    
    for (int i = 0; i < 3; i++)
    {
        int a, b;
        cin >> a >> b;
        map[a].push_back(b);
    }
    
    for (int i = 1; i <=3; i++)
    {
        for (int j : map[i])
            cout << j << " ";
        cout << "\n";
    }
 }

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입력: 
1 3
1 4
2 5

출력:
3 4
5

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