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답안 #231111

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
231111 2020-05-12T18:40:02 Z MKopchev 캥거루 (CEOI16_kangaroo) C++14
100 / 100
 62 ms 16792 KB 
#include<bits/stdc++.h>
using namespace std;

const int nmax=2e3+42,mod=1e9+7;

int dp[nmax][nmax];

int n,beg,en;

int rec(int to_place,int groups)
{
    if(to_place>n)return groups==1;

    if(dp[to_place][groups]!=-1)return dp[to_place][groups];

    long long ret=0;
    if(to_place==beg||to_place==en)
    {
        ret=rec(to_place+1,groups);//place with the first/last group
        ret+=rec(to_place+1,groups+1);//make new group
    }
    else
    {
        ret=1LL*(groups-1)*rec(to_place+1,groups-1);//merge 2 groups

        int positions=groups+1;

        if(to_place>beg)positions--;

        if(to_place>en)positions--;

        if(positions>0)ret+=1LL*positions*rec(to_place+1,groups+1);//create new group

    }


    ret=ret%mod;
    dp[to_place][groups]=ret;
    return ret;
}
int main()
{
    scanf("%i%i%i",&n,&beg,&en);

    memset(dp,-1,sizeof(dp));

    printf("%i\n",rec(1,0));
    return 0;
}

Compilation message

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:43:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%i%i%i",&n,&beg,&en);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 16640 KB Output is correct
2 Correct 13 ms 16640 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 16640 KB Output is correct
2 Correct 13 ms 16640 KB Output is correct
3 Correct 14 ms 16640 KB Output is correct
4 Correct 13 ms 16640 KB Output is correct
5 Correct 14 ms 16640 KB Output is correct
6 Correct 14 ms 16640 KB Output is correct
7 Correct 13 ms 16640 KB Output is correct
8 Correct 14 ms 16640 KB Output is correct
9 Correct 14 ms 16640 KB Output is correct
10 Correct 14 ms 16640 KB Output is correct
11 Correct 14 ms 16640 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 16640 KB Output is correct
2 Correct 13 ms 16640 KB Output is correct
3 Correct 14 ms 16640 KB Output is correct
4 Correct 13 ms 16640 KB Output is correct
5 Correct 14 ms 16640 KB Output is correct
6 Correct 14 ms 16640 KB Output is correct
7 Correct 13 ms 16640 KB Output is correct
8 Correct 14 ms 16640 KB Output is correct
9 Correct 14 ms 16640 KB Output is correct
10 Correct 14 ms 16640 KB Output is correct
11 Correct 14 ms 16640 KB Output is correct
12 Correct 13 ms 16640 KB Output is correct
13 Correct 13 ms 16640 KB Output is correct
14 Correct 14 ms 16640 KB Output is correct
15 Correct 14 ms 16640 KB Output is correct
16 Correct 14 ms 16640 KB Output is correct
17 Correct 15 ms 16640 KB Output is correct
18 Correct 14 ms 16792 KB Output is correct
19 Correct 14 ms 16640 KB Output is correct
20 Correct 14 ms 16640 KB Output is correct

Subtask #4
49.0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 16640 KB Output is correct
2 Correct 13 ms 16640 KB Output is correct
3 Correct 14 ms 16640 KB Output is correct
4 Correct 13 ms 16640 KB Output is correct
5 Correct 14 ms 16640 KB Output is correct
6 Correct 14 ms 16640 KB Output is correct
7 Correct 13 ms 16640 KB Output is correct
8 Correct 14 ms 16640 KB Output is correct
9 Correct 14 ms 16640 KB Output is correct
10 Correct 14 ms 16640 KB Output is correct
11 Correct 14 ms 16640 KB Output is correct
12 Correct 13 ms 16640 KB Output is correct
13 Correct 13 ms 16640 KB Output is correct
14 Correct 14 ms 16640 KB Output is correct
15 Correct 14 ms 16640 KB Output is correct
16 Correct 14 ms 16640 KB Output is correct
17 Correct 15 ms 16640 KB Output is correct
18 Correct 14 ms 16792 KB Output is correct
19 Correct 14 ms 16640 KB Output is correct
20 Correct 14 ms 16640 KB Output is correct
21 Correct 19 ms 16640 KB Output is correct
22 Correct 19 ms 16640 KB Output is correct
23 Correct 23 ms 16768 KB Output is correct
24 Correct 54 ms 16768 KB Output is correct
25 Correct 53 ms 16768 KB Output is correct
26 Correct 52 ms 16768 KB Output is correct
27 Correct 62 ms 16768 KB Output is correct
28 Correct 40 ms 16768 KB Output is correct