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 <iostream>
#include <cmath>
#include <algorithm>
#include <string>
#include <vector>
#include <iomanip>
#include <set>
#include <map>
 
#define ll long long
#define cint const int
#define ld long double
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define pb push_back
#define ppb pop_back
#define fi first
#define se second
 
using namespace std;
 
typedef vector <long long> vll;
typedef vector <string> vs;
typedef vector <char> vc;
typedef set <int> si;
typedef set <string> ss;
typedef pair <int, int> pi;
//typedef pair <long long, long long> pll;
//typedef pair <int, long long> pil;
//typedef pair <int, string> pis;
//typedef pair <int, char> pic;
//typedef pair <long long, int> pli;
//typedef pair <long long, string> pls;
//typedef pair <long long, char> plc;
//typedef pair <string, int> psi;
//typedef pair <string, long long> psl;
//typedef pair <string, char> psc;
//typedef pair <char, int> pci;
//typedef pair <char, long long> pcl;
//typedef pair <char, string> pcs;
int a, b;
int main () {
	cin >> a >> b;
	cout << 6 - (a + b);
	return 0;
}