Submission #1172660

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172660		Nurislam	NoM (RMI21_nom)	C++20	0 / 100	0 ms	324 KiB

Main

#include <bits/stdc++.h>

using namespace std;


#define int long long
#define pb push_back

int inf = 1e18; 

const int mod = 1e9 + 7;

//struct bitt {
	//vector<int> t;
	//int n;
	//bitt (int N) : n(N+1) {
		//t.resize(n+2);
	//};
	
	//void upd(int i, int va) { i ++ ;
		//for(; i < n; i += (i & -i)) t[i] += va;
	//};
	
	//int get(int i) { i ++ ;
		//int res = 0;
		//for(; i > 0; i -= (i & -i)) res += t[i];
		//return res;
	//};
	
	//int get(int l, int r) { r--;
		//return get(r ) - get( -- l );
	//};
//};

void solve(){
	
	int n, m;
	cin >> n >> m;
	
	vector<int> a(n*2);
	iota(a.begin(), a.end(), 0);
	for(int&i:a)if(i>=n)i-=n;
	sort(a.begin(),a.end());
	
	int ans = 0;
	do{
		bool ok = 1;
		vector<int> v(n, -1);
		for(int i = 0; i < n*2; i ++ ) {
			if(v[a[i]] == -1)v[a[i]] = i;
			else if((i - v[a[i]])%m == 0)ok = 0;
		}
		ans += ok;
	}while(next_permutation(a.begin(), a.end()));
	
	
	cout << ans %mod << '\n';
};

signed main(){
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr); cout.tie(nullptr);
	int tt = 1;
	//cin >> tt;
	
	while(tt -- ){
		solve();
	};
	
};

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 18
• Subtask 5: 0 / 48