Submission #333482

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
333482	2020-12-06T08:32:48 Z	benson1029	Tents (JOI18_tents)	C++14	100 / 100	186 ms	71020 KB

tents

#include<bits/stdc++.h>
#define MOD ((long long)1e9+7)
using namespace std;
int n,m;
long long dp[3005][3005];
int main() {
	cin >> n >> m;
	dp[0][0] = 1LL;
	for(int i=0; i<n; i++) {
		for(int j=0; j<=m; j++) {
			if(j+2<=m) {
				dp[i+1][j+2] += (((m-j)*(m-j-1LL)/2)%MOD) * dp[i][j];
				dp[i+1][j+2] %= MOD;
			}
			if(j<m) {
				dp[i+1][j+1] += dp[i][j] * (m-j) * 4LL;
				dp[i+1][j+1] %= MOD;
			}
			if(i<n-1) {
				dp[i+2][j+1] += dp[i][j] * ((((long long)m-j)*(i+1))%MOD);
				dp[i+2][j+1] %= MOD;
			}
		}
		for(int j=0; j<=m; j++) {
			dp[i+1][j] += dp[i][j];
			dp[i+1][j] %= MOD;
		}
	}
	long long ans = 0;
	for(int j=1; j<=m; j++) {
		ans += dp[n][j];
	}
	cout << ans%MOD << endl;
}

Subtask #1

48.0 / 48.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	364 KB	Output is correct
2	Correct	1 ms	364 KB	Output is correct
3	Correct	1 ms	492 KB	Output is correct
4	Correct	1 ms	1132 KB	Output is correct
5	Correct	1 ms	748 KB	Output is correct
6	Correct	2 ms	1388 KB	Output is correct
7	Correct	1 ms	876 KB	Output is correct
8	Correct	2 ms	1516 KB	Output is correct
9	Correct	1 ms	876 KB	Output is correct
10	Correct	3 ms	1772 KB	Output is correct
11	Correct	1 ms	364 KB	Output is correct
12	Correct	3 ms	2284 KB	Output is correct

Subtask #2

52.0 / 52.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	364 KB	Output is correct
2	Correct	1 ms	364 KB	Output is correct
3	Correct	1 ms	492 KB	Output is correct
4	Correct	1 ms	1132 KB	Output is correct
5	Correct	1 ms	748 KB	Output is correct
6	Correct	2 ms	1388 KB	Output is correct
7	Correct	1 ms	876 KB	Output is correct
8	Correct	2 ms	1516 KB	Output is correct
9	Correct	1 ms	876 KB	Output is correct
10	Correct	3 ms	1772 KB	Output is correct
11	Correct	1 ms	364 KB	Output is correct
12	Correct	3 ms	2284 KB	Output is correct
13	Correct	1 ms	364 KB	Output is correct
14	Correct	7 ms	9964 KB	Output is correct
15	Correct	119 ms	55148 KB	Output is correct
16	Correct	9 ms	4076 KB	Output is correct
17	Correct	28 ms	12908 KB	Output is correct
18	Correct	42 ms	17152 KB	Output is correct
19	Correct	140 ms	62956 KB	Output is correct
20	Correct	113 ms	50924 KB	Output is correct
21	Correct	84 ms	33824 KB	Output is correct
22	Correct	74 ms	35516 KB	Output is correct
23	Correct	47 ms	27116 KB	Output is correct
24	Correct	181 ms	71020 KB	Output is correct
25	Correct	157 ms	61292 KB	Output is correct
26	Correct	155 ms	66668 KB	Output is correct
27	Correct	186 ms	69100 KB	Output is correct