Cod sursa(job #2401033)

Utilizator Bodo171Bogdan Pop Bodo171 Data 9 aprilie 2019 13:01:13
Problema Permutari2 Scor 70
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.08 kb
#include <iostream>
#include <fstream>
using namespace std;
const int nmax=305;
const int mod=10007;
const int mod2=mod*mod;
int fact[nmax],sol[nmax];
int dp[nmax][nmax],c[nmax][nmax];
int n,k,i,j,ind;
void prc()
{
    fact[0]=1;
    for(i=1;i<=n;i++)
        fact[i]=(fact[i-1]*i)%mod;
    for(i=0;i<=n;i++)
        for(j=0;j<=i;j++)
    {
        if(!j) c[i][j]=1;
        else c[i][j]=(c[i-1][j-1]+c[i-1][j])%mod;
    }
}
int main()
{
    ifstream f("permutari2.in");
    ofstream g("permutari2.out");
    f>>n>>k;
    prc();
    dp[0][0]=1;
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=n;j++)
        {
            for(ind=0;ind<j;ind++)
           {
                dp[i][j]=(dp[i][j]+dp[i-1][ind]*fact[j-ind]);
                if(dp[i][j]>=mod2)
                    dp[i][j]-=mod2;
            }
           dp[i][j]%=mod;
        }
        sol[i]=dp[i][n];
    }
    for(i=n;i>=k;i--)
        for(j=i+1;j<=n;j++)
    {
        sol[i]=(sol[i]-sol[j]*c[j-1][i-1])%mod;
        if(sol[i]<0)
            sol[i]+=mod;
    }
    g<<sol[k];
    return 0;
}