Submission #762689

#	Time	Username	Problem	Language	Result	Execution time	Memory
762689		a_aguilo	A Huge Tower (CEOI10_tower)	C++14	100 / 100	101 ms	14748 KiB

tower

#include<bits/stdc++.h>

using namespace std;

int N, D;
int MOD = 1e9 + 9;

int main(){
	ios_base::sync_with_stdio(false);
    cin.tie(NULL);
	
	cin >> N >> D;
	long long a[N];
	long long b[N];
	for(int i = 0; i < N; ++i) cin >> a[i];
	sort(a, a + N);
	int left = 0; int right = 0;
	for(int i = 0; i < N; ++i){
		while(right < N and a[right] >= a[i]-D)right++;
		while(a[left] < a[i]-D) left++;
		b[i] = (right-left)%MOD;
	}
	long long dp[N];
	dp[0] = 1;
	for(int i = 1; i < N; ++i){
		dp[i] = (dp[i-1]*(b[i] + 1 - (N - i)))%MOD;
		//cout << b[i] << " " << dp[i] << endl;
	}
	cout << dp[N-1] << endl;
	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5