Submission #696521

# Submission time Handle Problem Language Result Execution time Memory
696521 2023-02-06T17:28:08 Z lucri Ruins 3 (JOI20_ruins3) C++17
58 / 100
3339 ms 524288 KB
#include <bits/stdc++.h>
#define MOD  1000000007
using namespace std;
unordered_map<long long,int>ma;
long long putere(long long a,long long b)
{
    if(b==0)
        return 1;
    long long p=putere(a,b/2);
    p*=p;
    p%=MOD;
    if(b%2)
    {
        p*=a;
        p%=MOD;
    }
    return p;
}
long long fact[610],comb[610][610];
void factorial()
{
    fact[0]=1;
    for(long long i=1;i<=600;++i)
        fact[i]=fact[i-1]*i%MOD;
}
long long combinari(long long n,long long m)
{
    long long ans=1;
    ans=fact[n];
    ans*=putere(fact[m],MOD-2);
    ans%=MOD;
    ans*=putere(fact[n-m],MOD-2);
    ans%=MOD;
    return ans;
}
long long n,v[610];
long long cod(long long step,long long nrstack,long long ppoz,bool exista)
{
    return (((step-1)*600+nrstack-1)*600+ppoz-1)*2+exista-1;
}
long long raspunde(long long step,long long nrstack,long long ppoz,bool exista)
{
    if(ma.find(cod(step,nrstack,ppoz,exista))!=ma.end())
        return ma[cod(step,nrstack,ppoz,exista)];
    if(step==n)
    {
        ma[cod(step,nrstack,ppoz,exista)]=1;
        return 1;
    }
    long long ans=0;
    long long ramas=n-step-nrstack;
    long long posibileInceput=v[ppoz]-1-(2*step-step+ppoz-1-nrstack);
    if(exista==false)
    {
        if(ramas>=3)
            ans=(ans+comb[ramas-1][2]*raspunde(step+1,nrstack+1,ppoz,false))%MOD;
        if(ramas>=2)
            ans=(ans+(ramas-1)*raspunde(step+1,nrstack+1,ppoz,true))%MOD;
        if(posibileInceput>=2&&nrstack>=1)
            ans=(ans+comb[posibileInceput][2]*raspunde(step+1,nrstack-1,ppoz,false))%MOD;
        if(posibileInceput&&nrstack>=1&&ramas>=1)
        {
            if(ramas-1)
                ans=(ans+posibileInceput*(ramas-1)%MOD*raspunde(step+1,nrstack,ppoz,false))%MOD;
            ans=(ans+posibileInceput*raspunde(step+1,nrstack,ppoz,true))%MOD;
        }
        else if(posibileInceput&&ramas>=1)
        {
            if(step==n-1)
            {
                ma[cod(step,nrstack,ppoz,exista)]=1;
                return 1;
            }
            if(ramas-1)
                ans=(ans+posibileInceput*(ramas-1)%MOD*raspunde(step+1,nrstack,ppoz,false))%MOD;
            long long q=putere(comb[n-ppoz][step+1-ppoz],MOD-2);
            for(int newppoz=ppoz+1;newppoz<=step+2;++newppoz)
                ans=(ans+comb[n-newppoz][step+2-newppoz]*q%MOD*posibileInceput%MOD*raspunde(step+1,nrstack,newppoz,false))%MOD;
        }
    }
    else
    {
        if(ramas>=2)
            ans=(ans+comb[ramas][2]*raspunde(step+1,nrstack+1,ppoz,true))%MOD;
        if(posibileInceput>=2)
        {
            if(nrstack>=2)
                ans=(ans+comb[posibileInceput][2]*raspunde(step+1,nrstack-1,ppoz,true))%MOD;
            else
            {
                if(step==n-1)
                {
                    ma[cod(step,nrstack,ppoz,exista)]=1;
                    return 1;
                }
                long long q=putere(comb[n-ppoz][step+1-ppoz],MOD-2);
                for(int newppoz=ppoz+1;newppoz<=step+2;++newppoz)
                    ans=(ans+comb[n-newppoz][step+2-newppoz]*q%MOD*comb[posibileInceput][2]%MOD*raspunde(step+1,nrstack-1,newppoz,false))%MOD;
            }
        }
        if(posibileInceput&&ramas>=1)
            ans=(ans+posibileInceput*ramas%MOD*raspunde(step+1,nrstack,ppoz,true))%MOD;
    }
    ma[cod(step,nrstack,ppoz,exista)]=ans;
    return ans;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    factorial();
    cin>>n;
    for(int i=1;i<=n;++i)
        cin>>v[i];
    for(int i=0;i<=n;++i)
        for(int j=0;j<=i;++j)
            comb[i][j]=combinari(i,j);
    cout<<raspunde(0,0,1,false);
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 4 ms 1236 KB Output is correct
12 Correct 4 ms 1108 KB Output is correct
13 Correct 4 ms 1236 KB Output is correct
14 Correct 4 ms 1108 KB Output is correct
15 Correct 1 ms 596 KB Output is correct
16 Correct 2 ms 724 KB Output is correct
17 Correct 2 ms 596 KB Output is correct
18 Correct 10 ms 2096 KB Output is correct
19 Correct 9 ms 1968 KB Output is correct
20 Correct 8 ms 1968 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 4 ms 1236 KB Output is correct
12 Correct 4 ms 1108 KB Output is correct
13 Correct 4 ms 1236 KB Output is correct
14 Correct 4 ms 1108 KB Output is correct
15 Correct 1 ms 596 KB Output is correct
16 Correct 2 ms 724 KB Output is correct
17 Correct 2 ms 596 KB Output is correct
18 Correct 10 ms 2096 KB Output is correct
19 Correct 9 ms 1968 KB Output is correct
20 Correct 8 ms 1968 KB Output is correct
21 Correct 836 ms 164972 KB Output is correct
22 Correct 607 ms 114388 KB Output is correct
23 Correct 620 ms 114304 KB Output is correct
24 Correct 1217 ms 228096 KB Output is correct
25 Correct 82 ms 3140 KB Output is correct
26 Correct 80 ms 3172 KB Output is correct
27 Correct 81 ms 3132 KB Output is correct
28 Correct 138 ms 22520 KB Output is correct
29 Correct 79 ms 3196 KB Output is correct
30 Runtime error 3339 ms 524288 KB Execution killed with signal 9
31 Halted 0 ms 0 KB -