Submission #46443

# Submission time Handle Problem Language Result Execution time Memory
46443 2018-04-20T20:13:10 Z alex99 Calvinball championship (CEOI15_teams) C++14
10 / 100
13 ms 9172 KB
#include <iostream>
using namespace std;
int N;
int A[10005];
int DP[10005];
int Fact[10005], Inv[10005];
const int MOD = 1000007;
int Power[10005];
int C[1005][1005];
int power(int n, int p)
{
    int sol = 1;
    while(p)
    {
        if(p % 2 == 1)
        {
            sol = (1LL * sol * n) % MOD;
        }
        p /= 2;
        n = (1LL * n * n) % MOD;
    }
    return sol;
}
void Read()
{
    cin >> N;
    for(int i = 1; i <= N; i++)
        cin >> A[i];
}
void precalcFact()
{
    Fact[0] = 1;
    for(int i = 1; i <= N; i++)
        Fact[i] = (1LL * Fact[i - 1] * i) % MOD;
    Inv[N] = power(Fact[N], MOD - 2);
    for(int i = N - 1; i >= 0; i--)
    {
        Inv[i] = (1LL * Inv[i + 1] * (i + 1)) % MOD;
    }
}

int Comb(int n, int k)
{
    return C[n][k];
}
inline void Add(int& x, int y)
{
    x += y;
    if(x >= MOD)
        x -= MOD;
}
void precalcDP()
{
    DP[0] = 1;
    for(int i = 1; i <= N; i++)
    {
        for(int j = 0; j < i; j++)
        {
            Add(DP[i], (1LL * DP[i - 1 - j] * Comb(i - 1, j)) % MOD);
        }
    }
}
void precalcComb()
{
    for(int i = 0; i <= N; i++)
        C[i][0] = 1;
    for(int i = 1; i <= N; i++)
        for(int j = 1; j <= i; j++)
        {
            C[i][j] = C[i - 1][j - 1] + C[i - 1][j];
            if(C[i][j] >= MOD)
                C[i][j] -= MOD;
        }
}
void Solve()
{
    int nb = 1, ans = 1;
    Power[0] = 1;
    for(int j = 1; j <= N; j++)
        Power[j] = j;
    for(int i = 2; i <= N; i++)
    {
        if(A[i] == 1)
            continue;
        int aux = 0;
        for(int j = 0; j <= N - i; j++)
        {
            Add(aux, (1LL * Comb(N - i, j) * DP[j] * Power[N - i - j]) % MOD);
        }
        Add(ans, (1LL * aux * (A[i] - 1)) % MOD);
        if(A[i] == nb + 1)
        {
            for(int j = 1; j <= N - i; j++)
            {
                Power[j] = (1LL * Power[j] * j) % MOD;
            }
            ++nb;
        }
    }
    cout << ans << "\n";
}
int main()
{
    Read();
    precalcFact();
    precalcComb();
    precalcDP();
    Solve();
    //cout << DP[N] << "\n";
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 416 KB Output is correct
4 Correct 2 ms 492 KB Output is correct
5 Correct 13 ms 492 KB Output is correct
6 Correct 2 ms 544 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 544 KB Output is correct
2 Incorrect 2 ms 544 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 544 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 952 KB Output isn't correct
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 952 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 4 ms 2540 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 10 ms 4576 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 12 ms 8940 KB Execution killed with signal 11 (could be triggered by violating memory limits)
# Verdict Execution time Memory Grader output
1 Runtime error 10 ms 9024 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 13 ms 9172 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -