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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <cmath>
#include <string>
#include <algorithm>
#include <set>
#include <queue>
#include <stack>
#include <utility>
#include <tuple>
#include <random>
#include <map>
using namespace std;

const double pi = acos(-1);
#define nyan cout << "(=^•ω•^=)" << endl;
#define int long long
#define rep(i, n) for(int i = 0; i < n; i++)
#define loop while(true)
#define YN(f) f?cout<<"YES"<<endl:cout<<"NO"<<endl;
#define yn(f) f?cout<<"Yes"<<endl:cout<<"No"<<endl;

int a[4];
string s;
bool f=false;

signed main(){
	cin>>a[0]>>a[1]>>a[2]>>a[3];
	sort(a,a+4);
	if(a[0]==1&&a[1]==4&&a[2]==7&&a[3]==9)f=true;
	YN(f);
	return 0;
}