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 C++14 (GCC 5.4.1) (judge verdict: Accepted)




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

#define mod 998244353

long long dp[300001];

int a[300001];

int N;

long long f(int i) {
    stack<int> st;
    
    for(int i = 0; i < N; i++) {
        if(st.size() > 0) {
            if(st.top() % 2 == a[i] % 2) {
                st.pop();
            }else st.push(a[i]);
        }else st.push(a[i]);
    }
    long long cnt = 0;
    while(!st.empty()) {
        if(st.top() % 2) cnt++;
        st.pop();
    }
    return cnt;

}


int main() {
    // oh hi mark
    int a,b; cin >> a >> b;
    cout << 6 - a -b  << endl;
    return 0;
}