Make a simple program in Java that counts infected computers on a computer network. The virus spreads through the network, and every computer that is connected to an infected computer is infected.

For example, there are seven computers. If computer #1 is infected, computer #3 and 6 will be infected through infection of computer #2 and 5. Computer #4 and 7 are safe. So, totally four computers are infected. Please implement your algorithm in Java but not use API. Input: In the first line, a number of computers is given and there is no limit. The second line is a number of edges that represents a connection between two computers. After second line, each line has two numbers that represent two computers that are connected. In the last line, a computer number is given as the first computer that is infected. Ouput: Number of computers infected by the first infected computer.

Please use basic statements for beginners: if/else, while loops, for loops, basic arrays, and try to only use import java.util.Scanner;

Example

Input:

7

6

1 2

2 3

1 5

5 2

5 6

4 7

1

Output: 4