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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

namespace A___Round_One
{
    class Program
    {
        static void Main (string[] args)
        {
            var c = new int[] {1,2,3};
            var a = int.Parse (Console.ReadLine ());
            var b = int.Parse (Console.ReadLine ());
            for (var i = 0; i < 3; i++)
            {
                if (c[i] != a && c[i] != b)
                {
                    Console.WriteLine (c[i]);
                    break;
                }
            }
        }
    }
}