oj.uz

답안 #377224

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
377224 2021-03-13T13:41:09 Z CaroLinda 캥거루 (CEOI16_kangaroo) C++14
100 / 100
 28 ms 23020 KB 
#include <bits/stdc++.h>

const int MAXN = 2010 ;
const int MOD = 1e9+7 ;

using namespace std ;

int N , S , T ;
long long dp[MAXN][MAXN] ;

int main()
{
	scanf("%d %d %d", &N , &S, &T ) ;

	if( S > T ) swap(S,T) ;

	dp[0][1] = 1 ;

	for(int i = 1 ; i < N ; i++ )
		for(int j= 1 ; j <= N-i ; j++ )
		{
			long long &ptr = dp[i][j] ;
			long long fat ;

			if( i == T || i == S )
			{
				ptr = dp[i-1][j+1] + dp[i-1][j] ;
				if( ptr >= MOD ) ptr -= MOD ;
				continue ;
			}
		
			//creating new component
			fat = (j-1) + ( i > S ) + (i > T ) ;
			ptr = (fat * dp[i-1][j+1] ) % MOD ;

			//joining two components
			ptr += (dp[i-1][j-1] * (j-1) ) % MOD ;
			ptr %= MOD ;

		}

	long long ans = dp[N-1][1] ;

	printf("%lld\n", ans ) ;
}

Compilation message

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:13:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |  scanf("%d %d %d", &N , &S, &T ) ;
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 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 492 KB Output is correct
5 Correct 1 ms 492 KB Output is correct
6 Correct 1 ms 492 KB Output is correct
7 Correct 1 ms 492 KB Output is correct
8 Correct 1 ms 492 KB Output is correct
9 Correct 1 ms 492 KB Output is correct
10 Correct 1 ms 492 KB Output is correct
11 Correct 1 ms 492 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 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 492 KB Output is correct
5 Correct 1 ms 492 KB Output is correct
6 Correct 1 ms 492 KB Output is correct
7 Correct 1 ms 492 KB Output is correct
8 Correct 1 ms 492 KB Output is correct
9 Correct 1 ms 492 KB Output is correct
10 Correct 1 ms 492 KB Output is correct
11 Correct 1 ms 492 KB Output is correct
12 Correct 2 ms 1260 KB Output is correct
13 Correct 1 ms 1260 KB Output is correct
14 Correct 1 ms 1260 KB Output is correct
15 Correct 1 ms 1304 KB Output is correct
16 Correct 1 ms 1260 KB Output is correct
17 Correct 1 ms 1260 KB Output is correct
18 Correct 1 ms 1132 KB Output is correct
19 Correct 1 ms 1260 KB Output is correct
20 Correct 2 ms 1280 KB Output is correct

Subtask #4
49.0 / 49.0

# 결과 실행 시간 메모리 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 492 KB Output is correct
5 Correct 1 ms 492 KB Output is correct
6 Correct 1 ms 492 KB Output is correct
7 Correct 1 ms 492 KB Output is correct
8 Correct 1 ms 492 KB Output is correct
9 Correct 1 ms 492 KB Output is correct
10 Correct 1 ms 492 KB Output is correct
11 Correct 1 ms 492 KB Output is correct
12 Correct 2 ms 1260 KB Output is correct
13 Correct 1 ms 1260 KB Output is correct
14 Correct 1 ms 1260 KB Output is correct
15 Correct 1 ms 1304 KB Output is correct
16 Correct 1 ms 1260 KB Output is correct
17 Correct 1 ms 1260 KB Output is correct
18 Correct 1 ms 1132 KB Output is correct
19 Correct 1 ms 1260 KB Output is correct
20 Correct 2 ms 1280 KB Output is correct
21 Correct 4 ms 4716 KB Output is correct
22 Correct 4 ms 5100 KB Output is correct
23 Correct 5 ms 5612 KB Output is correct
24 Correct 25 ms 23020 KB Output is correct
25 Correct 25 ms 23020 KB Output is correct
26 Correct 25 ms 23020 KB Output is correct
27 Correct 28 ms 22896 KB Output is correct
28 Correct 15 ms 15084 KB Output is correct