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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#791668#8023. The Journey of Geor AutumnUnstalianRE 0ms3552kbC++201.1kb2024-11-28 20:13:442024-11-28 20:13:44

Judging History

This is the latest submission verdict.

  • [2024-11-28 20:13:44]
  • Judged
  • Verdict: RE
  • Time: 0ms
  • Memory: 3552kb
  • [2024-11-28 20:13:44]
  • Submitted

answer

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl '\n'
#define maxn
const int mod = 998244353;
int n, m, k;
int quick(int a, int b){
	int res = 1;
	while (b){
		if(b & 1) {
			res = res * a % mod;
		}
		a = a * a % mod;
		b >>= 1;
	}
	return res;
}
int inv(int x){
	return quick(x, mod - 2) % mod;
}
void solve(){
	cin >> n>> k;
	vector<int> sum(n + 1, 0), fact(n + 1, 0);
	fact[1] = 1;
	for (int i = 2;i <= n;i ++){
		fact[i] = (fact[i - 1] * i) % mod;
		// cout << fact[i]<<endl;
	}
	for (int i = 1;i <= k;i ++){
		sum[i] = (sum[i - 1] + 1)% mod;
		// cout << sum[i]<<endl;
	}
	if(n <= k){
		cout << fact[n]<<endl;
		return;
	}
	int res = 0;
	// cout << (inv(6)) % mod<<endl;;
	for (int i = k + 1;i <= n;i ++){
		res = (sum[i - 1] - sum[i - k - 1] + mod) % mod;
		res = (res * fact[i - 1]) % mod;
		// cout << "!!! "<<res <<" "<< (sum[i - 1] - sum[i - k - 1] + mod) % mod<<endl;
		sum[i] = (sum[i - 1] + (res * inv(fact[i])) % mod + mod) % mod;
	}
	cout << res<<endl;
}
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	int T = 1;
	// cin >> T;
	while (T --)
		solve();
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3552kb

input:

1 1

output:

1

result:

ok "1"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3544kb

input:

1 2

output:

1

result:

ok "1"

Test #3:

score: -100
Runtime Error

input:

1 3

output:


result: