Problem:
Score: 100 points

Problem Statement

Takahashi is solving quizzes. He has easily solved all but the last one.

The last quiz has three choices: 1, 2, and 3.

With his supernatural power, Takahashi has found out that the choices A and B are both wrong.

Print the correct choice for this problem.

Constraints

Each of the numbers A and B is 1, 2, or 3.

A and B are different.

Input

Input is given from Standard Input in the following format:

A
B

Output

Print the correct choice.

Sample Input 1

3
1

Sample Output 1

2

When we know 3 and 1 are both wrong, the correct choice is 2.

Sample Input 2

1
2

Sample Output 2

3

Solution in Python (3.4.3) (judge verdict: Runtime Error)

#include<bits/stdc++.h>
using namespace std;
#define int long long

signed main(void){
    int a,b; cin >> a >> b;
    for (int i=1;i<=3;i++){
        if(i!=a && i !=b){
            cout << i << endl;
            return 0;
        }
    }
    return 0;
}