oj.uz

답안 #219736

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
219736 2020-04-06T07:49:02 Z patrikpavic2 Tents (JOI18_tents) C++17
100 / 100
 245 ms 35960 KB 
#include <cstdio>
#include <cstring>

using namespace std;

typedef long long ll;

const int N = 3005;
const int MOD = 1e9 + 7;

inline int add(int A,int B){
	if(A + B >= MOD) return A + B - MOD;
	return A + B;
}

inline int mul(int A,int B){
	return (ll)A * B % MOD;
}

inline int sub(int A,int B){
	if(A - B < 0) return A - B + MOD;
	return A - B;
}

int dp[N][N], inv2 = (MOD + 1) / 2;

int f(int a,int b,int sm = 0){
	if(a < 0 || b < 0) return 0;
	if(!a) return 1;
	if(dp[a][b] != -1) return dp[a][b];
	return dp[a][b] = add(add(add(mul(f(a - 2, b - 1), (a - 1) * b), mul(f(a - 1, b - 2), b * (b - 1) / 2)), mul(4 * b, f(a - 1, b - 1))), f(a - 1, b));	
}

int main(){
	memset(dp, -1, sizeof(dp));
	int x, y; scanf("%d%d", &x, &y);
	printf("%d\n", sub(f(x, y), 1));
}

Compilation message

tents.cpp: In function 'int main()':
tents.cpp:36:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int x, y; scanf("%d%d", &x, &y);
            ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
48.0 / 48.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 35584 KB Output is correct
2 Correct 22 ms 35584 KB Output is correct
3 Correct 22 ms 35584 KB Output is correct
4 Correct 21 ms 35712 KB Output is correct
5 Correct 24 ms 35584 KB Output is correct
6 Correct 21 ms 35712 KB Output is correct
7 Correct 20 ms 35584 KB Output is correct
8 Correct 22 ms 35584 KB Output is correct
9 Correct 22 ms 35712 KB Output is correct
10 Correct 22 ms 35712 KB Output is correct
11 Correct 21 ms 35584 KB Output is correct
12 Correct 23 ms 35712 KB Output is correct

Subtask #2
52.0 / 52.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 35584 KB Output is correct
2 Correct 22 ms 35584 KB Output is correct
3 Correct 22 ms 35584 KB Output is correct
4 Correct 21 ms 35712 KB Output is correct
5 Correct 24 ms 35584 KB Output is correct
6 Correct 21 ms 35712 KB Output is correct
7 Correct 20 ms 35584 KB Output is correct
8 Correct 22 ms 35584 KB Output is correct
9 Correct 22 ms 35712 KB Output is correct
10 Correct 22 ms 35712 KB Output is correct
11 Correct 21 ms 35584 KB Output is correct
12 Correct 23 ms 35712 KB Output is correct
13 Correct 21 ms 35712 KB Output is correct
14 Correct 22 ms 35840 KB Output is correct
15 Correct 153 ms 35840 KB Output is correct
16 Correct 23 ms 35584 KB Output is correct
17 Correct 34 ms 35712 KB Output is correct
18 Correct 54 ms 35712 KB Output is correct
19 Correct 173 ms 35840 KB Output is correct
20 Correct 138 ms 35840 KB Output is correct
21 Correct 88 ms 35712 KB Output is correct
22 Correct 103 ms 35840 KB Output is correct
23 Correct 66 ms 35840 KB Output is correct
24 Correct 244 ms 35912 KB Output is correct
25 Correct 172 ms 35840 KB Output is correct
26 Correct 201 ms 35840 KB Output is correct
27 Correct 245 ms 35960 KB Output is correct