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 C (Clang 3.8.0) (judge verdict: Accepted)

#include <stdio.h>
#include <stdint.h>

int main (void)
{
    int N1, N2, N3, N4;
    uint16_t flag = 0;

    scanf("%d %d %d %d", &N1, &N2, &N3, &N4);

    flag = (1 << N1) | (1 << N2) | (1 << N3) | (1 << N4);

    if (flag == ((1 << 1) | (1 << 9) | (1 << 7) | (1 << 4))) {
        puts("YES");
    } else {
        puts("NO");
    }
}