Problem:
Score : 100 points

Problem Statement

You are given four digits N_1, N_2, N_3 and N_4. Determine if these can be arranged into the sequence of digits "1974".

Constraints

0 \leq N_1, N_2, N_3, N_4 \leq 9

N_1, N_2, N_3 and N_4 are integers.

Input

Input is given from Standard Input in the following format:

N_1 N_2 N_3 N_4

Output

If N_1, N_2, N_3 and N_4 can be arranged into the sequence of digits "1974", print YES; if they cannot, print NO.

Sample Input 1

1 7 9 4

Sample Output 1

YES

We can get 1974 by swapping N_2 and N_3.

Sample Input 2

1 9 7 4

Sample Output 2

YES

We already have 1974 before doing anything.

Sample Input 3

1 2 9 1

Sample Output 3

NO

Sample Input 4

4 9 0 8

Sample Output 4

NO

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;
public class Main {
	public static void main(String[] args)
	{
		//変数
		int count=0;
		boolean sw=false;
		String answer="";
		int e=0;
		int f=0;
		int g=0;
		int h=0;
		//List<Integer> hb=new ArrayList<Integer>();
		//long a=0;
		//int af=Integer.MAX_VALUE;
		//入力
		Scanner sc = new Scanner(System.in);
		int a=sc.nextInt();
		int b=sc.nextInt();
		int c=sc.nextInt();
		int d=sc.nextInt();
		//int [][] cost =new int[N-1][2];
		//処理
		if(a==1 || b==1 || c==1 || d==1)
		{
			e=1;
		}
		if(a==9 || b==9 || c==9 || d==9)
		{
			f=1;
		}
		if(a==7 || b==7 || c==7 || d==7)
		{
			g=1;
		}
		if(a==4 || b==4 || c==4 || d==4)
		{
			h=1;
		}
		//
		if(e==1 && f==1 && g==1 && h==1)
		{
			answer="YES";
		}else
		{
			answer="NO";
		}
		// 出力
		System.out.println(answer);
	}
}