ACGO欢乐赛#42题解

Solution

发现 $4!=24$ 是 $24$ 的倍数，所以当 $x\ge4$ 时也一定符合，因此只要判断 $[x\ge24]$ 即可。

Code

#include <bits/stdc++.h>
#include <cstdio>
#define int long long
#define ull unsigned long long
#define mod 998244353
#define MOD 1000000007
using namespace std;
const int N = 2e6 + 5,maxn = 3e3 + 5;
const double goldnum = (sqrt (5) + 1) / 2;
inline int read ()
{
	int x = 0;
	bool f = 1;
	char c = getchar ();
	while (c < '0' || c > '9') f = (c == '-' ? !f : f),c = getchar ();
	while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + (c ^ 48),c = getchar ();
	return (f ? x : -x);
}
inline void write (int x)
{
	if (x < 0) putchar ('-'),x = -x;
	if (x > 9) write (x / 10);
	putchar (x % 10 + '0');
	return ;
}
signed main ()
{
	int n;
	cin >> n;
	cout << (n >= 4 ? "YES" : "NO");
	return 0;
}