oj.uz

Submission #839189

# Submission time Handle Problem Language Result Execution time Memory
839189 2023-08-29T02:55:32 Z guagua0407 Kangaroo (CEOI16_kangaroo) C++17
100 / 100
 20 ms 23092 KB 
//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

const int mxn=2005;
const int mod=1e9+7;
ll dp[mxn][mxn];
int cnt=0;

int main() {_
    int n,st,en;
    cin>>n>>st>>en;
    if(st>en) swap(st,en);
    dp[1][1]=1;
    if(1==st) cnt++;
    for(int i=1;i<n;i++){
        if(i+1==st){
            // new
            for(int j=1;j<=i;j++){
                dp[i+1][j+1]=(dp[i+1][j+1]+dp[i][j])%mod;
            }
            // continue
            for(int j=1;j<=i;j++){
                dp[i+1][j]=(dp[i+1][j]+dp[i][j]*j)%mod;
            }
            cnt++;
        }
        else if(i+1==en){
            // new
            for(int j=1;j<=i;j++){
                dp[i+1][j+1]=(dp[i+1][j+1]+dp[i][j])%mod;
            }
            // continue
            for(int j=1;j<=i;j++){
                dp[i+1][j]=(dp[i+1][j]+dp[i][j]*(j-1+(i==n-1 and j==1)))%mod;
            }
            cnt++;
        }
        else{
            // new
            for(int j=1;j<=i;j++){
                dp[i+1][j+1]=(dp[i+1][j+1]+dp[i][j])%mod;
            }
            // combine
            for(int j=1;j<=i;j++){
                dp[i+1][j-1]=(dp[i+1][j-1]+dp[i][j]*(j*(j-1)-(j-1)*cnt+(cnt==2 and i==n-1)))%mod;
            }
        }
    }
    cout<<dp[n][1]<<'\n';
    return 0;
}
//maybe its multiset not set

Compilation message

kangaroo.cpp: In function 'void setIO(std::string)':
kangaroo.cpp:12:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kangaroo.cpp:13:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 0 ms 468 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 0 ms 456 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 0 ms 468 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 0 ms 456 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 1236 KB Output is correct
13 Correct 1 ms 1108 KB Output is correct
14 Correct 1 ms 1236 KB Output is correct
15 Correct 1 ms 1236 KB Output is correct
16 Correct 1 ms 1236 KB Output is correct
17 Correct 1 ms 1228 KB Output is correct
18 Correct 1 ms 1108 KB Output is correct
19 Correct 1 ms 1232 KB Output is correct
20 Correct 2 ms 1228 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 0 ms 468 KB Output is correct
5 Correct 1 ms 460 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 0 ms 456 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 1 ms 468 KB Output is correct
11 Correct 1 ms 468 KB Output is correct
12 Correct 1 ms 1236 KB Output is correct
13 Correct 1 ms 1108 KB Output is correct
14 Correct 1 ms 1236 KB Output is correct
15 Correct 1 ms 1236 KB Output is correct
16 Correct 1 ms 1236 KB Output is correct
17 Correct 1 ms 1228 KB Output is correct
18 Correct 1 ms 1108 KB Output is correct
19 Correct 1 ms 1232 KB Output is correct
20 Correct 2 ms 1228 KB Output is correct
21 Correct 3 ms 4564 KB Output is correct
22 Correct 4 ms 5076 KB Output is correct
23 Correct 4 ms 5580 KB Output is correct
24 Correct 19 ms 23092 KB Output is correct
25 Correct 19 ms 23004 KB Output is correct
26 Correct 20 ms 22952 KB Output is correct
27 Correct 20 ms 22780 KB Output is correct
28 Correct 12 ms 15060 KB Output is correct