oj.uz

Submission #858901

# Submission time Handle Problem Language Result Execution time Memory
858901 2023-10-09T11:24:26 Z Tenis0206 Kangaroo (CEOI16_kangaroo) C++11
100 / 100
 24 ms 23132 KB 
#include <bits/stdc++.h>

using namespace std;

const int nmax = 2000;
const int Mod = 1e9 + 7;

int n,cs,cf;

long long dp[nmax + 5][nmax + 5];

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
#ifdef home
    freopen("nr.in","r",stdin);
    freopen("nr.out","w",stdout);
#endif // home
    cin>>n>>cs>>cf;
    if(cs > cf)
    {
        swap(cs,cf);
    }
    dp[0][0] = 1;
    for(int i=0; i<n; i++)
    {
        for(int nrg=0; nrg<=i; nrg++)
        {
            int val = i + 1;

            /// creez grup nou
            if(val == cs)
            {
                dp[i + 1][nrg + 1] += dp[i][nrg];
                dp[i + 1][nrg + 1] %= Mod;
            }
            else if(val == cf)
            {
                dp[i + 1][nrg + 1] += dp[i][nrg];
                dp[i + 1][nrg + 1] %= Mod;
            }
            else
            {
                if(val < cs)
                {
                    dp[i + 1][nrg + 1] += 1LL * dp[i][nrg] * (nrg + 1) % Mod;
                    dp[i + 1][nrg + 1] %= Mod;
                }
                else if(val < cf)
                {
                    dp[i + 1][nrg + 1] += 1LL * dp[i][nrg] * nrg % Mod;
                    dp[i + 1][nrg + 1] %= Mod;
                }
                else if(nrg > 1)
                {
                    dp[i + 1][nrg + 1] += 1LL * dp[i][nrg] * (nrg - 1) % Mod;
                    dp[i + 1][nrg + 1] %= Mod;
                }
            }

            /// unesc doua grupuri existente
            if(val != cs && val != cf && nrg > 1)
            {
                dp[i + 1][nrg - 1] += 1LL * dp[i][nrg] * (nrg - 1) % Mod;
                dp[i + 1][nrg - 1] %= Mod;
            }

            /// adaug la inceput
            if(val == cs)
            {
                dp[i + 1][nrg] += dp[i][nrg];
                dp[i + 1][nrg] %= Mod;
            }

            /// adaug la final
            if(val == cf)
            {
                dp[i + 1][nrg] += dp[i][nrg];
                dp[i + 1][nrg] %= Mod;
            }
        }
    }
     cout<<dp[n][1]<<'\n';
    return 0;
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 604 KB Output is correct
5 Correct 0 ms 600 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 0 ms 604 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 0 ms 604 KB Output is correct
10 Correct 0 ms 604 KB Output is correct
11 Correct 0 ms 604 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 604 KB Output is correct
5 Correct 0 ms 600 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 0 ms 604 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 0 ms 604 KB Output is correct
10 Correct 0 ms 604 KB Output is correct
11 Correct 0 ms 604 KB Output is correct
12 Correct 1 ms 1368 KB Output is correct
13 Correct 1 ms 1116 KB Output is correct
14 Correct 1 ms 1372 KB Output is correct
15 Correct 1 ms 1372 KB Output is correct
16 Correct 1 ms 1372 KB Output is correct
17 Correct 1 ms 1372 KB Output is correct
18 Correct 1 ms 1116 KB Output is correct
19 Correct 1 ms 1372 KB Output is correct
20 Correct 1 ms 1372 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 604 KB Output is correct
5 Correct 0 ms 600 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 0 ms 604 KB Output is correct
8 Correct 0 ms 604 KB Output is correct
9 Correct 0 ms 604 KB Output is correct
10 Correct 0 ms 604 KB Output is correct
11 Correct 0 ms 604 KB Output is correct
12 Correct 1 ms 1368 KB Output is correct
13 Correct 1 ms 1116 KB Output is correct
14 Correct 1 ms 1372 KB Output is correct
15 Correct 1 ms 1372 KB Output is correct
16 Correct 1 ms 1372 KB Output is correct
17 Correct 1 ms 1372 KB Output is correct
18 Correct 1 ms 1116 KB Output is correct
19 Correct 1 ms 1372 KB Output is correct
20 Correct 1 ms 1372 KB Output is correct
21 Correct 4 ms 4700 KB Output is correct
22 Correct 4 ms 4956 KB Output is correct
23 Correct 5 ms 5724 KB Output is correct
24 Correct 24 ms 23104 KB Output is correct
25 Correct 21 ms 23132 KB Output is correct
26 Correct 22 ms 22964 KB Output is correct
27 Correct 21 ms 22876 KB Output is correct
28 Correct 13 ms 15100 KB Output is correct