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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#232908#6410. Classical DP ProblemksunWA 1ms5900kbC++141.4kb2023-10-31 00:31:312023-10-31 00:31:31

Judging History

你现在查看的是最新测评结果

  • [2023-10-31 00:31:31]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:5900kb
  • [2023-10-31 00:31:31]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;

const long long mod=998244353;
long long n,a[5001],k,x,dp1[5001][5001],dp2[5001][5001],v[5001];
long long factorial(long long n)
{
    long long nr=1;
    for(long long i=1;i<=n;i++)
        nr=(nr*i)%mod;
    return nr;
}
void rotire()
{
    for(long long i=1;i<=n;i++)
    {
        long long j=1;
        while(j<=n and a[j]>=i)
            j++;
        v[i]=j-1;
    }
    for(int i=1;i<=n;i++)
        a[i]=v[i];
}
int main()
{
    cin>>n;
    for(long long i=1;i<=n;i++)
        cin>>a[i];
    reverse(a+1,a+n+1);
    for(long long i=1;i<=n;i++)
    {
        if(a[i]>=i)
            k=i;
        else
            break;
    }
    x=a[k+1];
    dp1[0][x]=1;
    for(long long i=0;i<=k;i++)
    {
        for(long long j=0;j<=x;j++)
        {
            if(j>0)
                dp1[i+1][j-1]+=dp1[i][j]*j;
            dp1[i+1][j]+=dp1[i][j]*(a[i+1]-j);
        }
    }
    rotire();
    x=a[k+1];
    dp2[0][x]=1;
    for(long long i=0;i<=k;i++)
    {
        for(long long j=0;j<=x;j++)
        {
            if(j>0)
                dp2[i+1][j-1]+=dp2[i][j]*j;
            dp2[i+1][j]+=dp2[i][j]*(a[i+1]-j);
        }
    }
    long long total=0;
    total=dp1[k][0]+dp2[k][0]-factorial(k);
    total%=mod;
    while(total<0)
        total+=mod;
    cout<<k<<" "<<total;
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 1ms
memory: 5448kb

input:

3
1 2 3

output:

2 6

result:

ok 2 number(s): "2 6"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5436kb

input:

1
1

output:

1 1

result:

ok 2 number(s): "1 1"

Test #3:

score: 0
Accepted
time: 1ms
memory: 5444kb

input:

2
1 1

output:

1 2

result:

ok 2 number(s): "1 2"

Test #4:

score: 0
Accepted
time: 1ms
memory: 5576kb

input:

2
2 2

output:

2 6

result:

ok 2 number(s): "2 6"

Test #5:

score: 0
Accepted
time: 1ms
memory: 5416kb

input:

3
1 1 1

output:

1 3

result:

ok 2 number(s): "1 3"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5464kb

input:

3
2 2 2

output:

2 9

result:

ok 2 number(s): "2 9"

Test #7:

score: 0
Accepted
time: 1ms
memory: 5432kb

input:

3
3 3 3

output:

3 48

result:

ok 2 number(s): "3 48"

Test #8:

score: 0
Accepted
time: 1ms
memory: 5468kb

input:

5
1 1 3 3 4

output:

3 47

result:

ok 2 number(s): "3 47"

Test #9:

score: 0
Accepted
time: 1ms
memory: 5588kb

input:

10
2 4 5 5 5 5 6 8 8 10

output:

5 864

result:

ok 2 number(s): "5 864"

Test #10:

score: 0
Accepted
time: 1ms
memory: 5452kb

input:

30
6 8 9 9 9 10 13 14 15 15 16 17 17 18 20 22 22 23 23 24 24 25 25 25 27 28 28 29 29 30

output:

17 986189864

result:

ok 2 number(s): "17 986189864"

Test #11:

score: -100
Wrong Answer
time: 0ms
memory: 5900kb

input:

123
1 1 1 2 2 3 3 6 6 7 7 7 8 8 9 9 10 10 10 11 12 12 12 13 14 14 14 14 16 17 17 17 17 17 18 19 20 20 21 21 22 22 22 23 23 23 25 25 26 27 27 28 28 28 28 29 29 30 31 31 31 32 33 33 33 34 35 35 35 36 37 37 38 39 39 39 39 40 41 41 42 42 42 43 44 48 48 50 52 53 55 56 57 57 57 58 65 68 71 74 75 76 76 82 ...

output:

42 859773399

result:

wrong answer 2nd numbers differ - expected: '287179924', found: '859773399'