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답안 #476645

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
476645 2021-09-27T22:24:33 Z thiago_bastos Tents (JOI18_tents) C++17
100 / 100
 233 ms 70660 KB 
#include "bits/stdc++.h"
 
using namespace std;
 
using i64 = long long;
using u64 = unsigned long long;
using i32 = int;
using u32 = unsigned;
using i16 = short;
using u16 = unsigned short;
using ld = long double;
using ii = pair<int, int>;

const int mod = 1e9 + 7, N = 3e3 + 1;

i64 dp[N][N];

int mod_sum(int x) {
	return x < mod ? x : x - mod;
}

void solve() {
	int h, w, ans = 0;
	
	cin >> h >> w;
	
	dp[h][w] = 1;
	
	for(int x = h; x >= 0; --x) {
		for(int y = w; y >= 0; --y) {
		
			if(x > 0 && y >= 2) {
				i64 ways = y * (y - 1LL) / 2 % mod * dp[x][y] % mod;
				dp[x - 1][y - 2] = (dp[x - 1][y - 2] + ways) % mod;
				ans = mod_sum(ans + ways);
			}
			
			if(x >= 2 && y > 0) {
				i64 ways = dp[x][y] * (x - 1) % mod * y % mod;
				dp[x - 2][y - 1] = (dp[x - 2][y - 1] + ways) % mod;
				ans = mod_sum(ans + ways);
			}
			
			if(x > 0 && y > 0) {
				i64 ways = 4LL * y * dp[x][y] % mod;
				dp[x - 1][y - 1] = (dp[x - 1][y - 1] + ways) % mod;
				ans = mod_sum(ans + ways);
			}
			
			if(x > 0) dp[x - 1][y] = mod_sum(dp[x - 1][y] + dp[x][y]);
		}
	}
	
	cout << ans << '\n';
}

int main() {
	ios_base :: sync_with_stdio(false);
	cin.tie(0);
	int t = 1;
	//cin >> t;
	while(t--) solve();
 	return 0;
}

Subtask #1
48.0 / 48.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 460 KB Output is correct
4 Correct 1 ms 1100 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 1 ms 1352 KB Output is correct
7 Correct 1 ms 716 KB Output is correct
8 Correct 1 ms 1356 KB Output is correct
9 Correct 1 ms 716 KB Output is correct
10 Correct 2 ms 1740 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 4 ms 2236 KB Output is correct

Subtask #2
52.0 / 52.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 460 KB Output is correct
4 Correct 1 ms 1100 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 1 ms 1352 KB Output is correct
7 Correct 1 ms 716 KB Output is correct
8 Correct 1 ms 1356 KB Output is correct
9 Correct 1 ms 716 KB Output is correct
10 Correct 2 ms 1740 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 4 ms 2236 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 6 ms 9664 KB Output is correct
15 Correct 147 ms 55144 KB Output is correct
16 Correct 10 ms 4044 KB Output is correct
17 Correct 43 ms 12736 KB Output is correct
18 Correct 45 ms 17004 KB Output is correct
19 Correct 184 ms 62956 KB Output is correct
20 Correct 145 ms 50808 KB Output is correct
21 Correct 91 ms 33708 KB Output is correct
22 Correct 92 ms 35424 KB Output is correct
23 Correct 55 ms 27048 KB Output is correct
24 Correct 227 ms 70660 KB Output is correct
25 Correct 174 ms 61152 KB Output is correct
26 Correct 199 ms 66516 KB Output is correct
27 Correct 233 ms 68824 KB Output is correct