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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#375668#5532. Kangaroosichengzhou100 ✓26ms26568kbC++142.8kb2024-04-03 14:44:042024-04-03 14:44:06

Judging History

你现在查看的是最新测评结果

  • [2024-04-03 14:44:06]
  • 评测
  • 测评结果:100
  • 用时:26ms
  • 内存:26568kb
  • [2024-04-03 14:44:04]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=2020,mod=1e9+7;
int n,cs,cf;
LL f[N][N];
int main()
{
    scanf("%d%d%d",&n,&cs,&cf);
    f[0][0]=1;
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<=i;j++)
        {
            if(i+1==cs)
            {
                if(cf<=i)
                {
                    if(j>=2)
                    {
                        f[i+1][j]+=f[i][j]*(j-1)%mod;
                        f[i+1][j]%=mod;
                    }else if(j==1&&i==n-1)
                    {
                        f[i+1][j]+=f[i][j]*j%mod;
                        f[i+1][j]%=mod;
                    }
                }else{
                    if(j>=1)
                    {
                        f[i+1][j]+=f[i][j]*j%mod;
                        f[i+1][j]%=mod;
                    }
                }
            }else if(i+1==cf)
            {
                if(cs<=i)
                {
                    if(j>=2)
                    {
                        f[i+1][j]+=f[i][j]*(j-1)%mod;
                        f[i+1][j]%=mod;
                    }else if(j==1&&i==n-1)
                    {
                        f[i+1][j]+=f[i][j]*j%mod;
                        f[i+1][j]%=mod;
                    }
                }else{
                    if(j>=1)
                    {
                        f[i+1][j]+=f[i][j]*j%mod;
                        f[i+1][j]%=mod;
                    }
                }
            }else{
                if(i<cs&&i<cf)
                {
                    if(j>=2)
                    {
                        f[i+1][j-1]+=j*(j-1)%mod*f[i][j]%mod;
                        f[i+1][j-1]%=mod;
                    }
                }else if(cs<=i&&cf<=i)
                {
                    if(j>=3)
                    {
                        f[i+1][j-1]+=((j-1)*(j-1)-(j-2)-1)%mod*f[i][j]%mod;
                        f[i+1][j-1]%=mod;
                    }else if(j==2&&i==n-1)
                    {
                        f[i+1][j-1]+=f[i][j]%mod;
                        f[i+1][j-1]%=mod;
                    }
                }else if(cs<=i)
                {
                    if(j>=2)
                    {
                        f[i+1][j-1]+=(j*(j-1)-(j-1))%mod*f[i][j]%mod;
                        f[i+1][j-1]%=mod;
                    }
                }else{
                    if(j>=2)
                    {
                        f[i+1][j-1]+=(j*(j-1)-(j-1))%mod*f[i][j]%mod;
                        f[i+1][j-1]%=mod;
                    }
                }
            }
            f[i+1][j+1]+=f[i][j];
            f[i+1][j+1]%=mod;
        }
    }
    printf("%lld\n",f[n][1]);
    return 0;
}

詳細信息

Subtask #1:

score: 6
Accepted

Test #1:

score: 6
Accepted
time: 0ms
memory: 3772kb

input:

7 3 6

output:

14

result:

ok 1 number(s): "14"

Subtask #2:

score: 30
Accepted

Dependency #1:

100%
Accepted

Test #2:

score: 30
Accepted
time: 1ms
memory: 3964kb

input:

39 36 32

output:

964903316

result:

ok 1 number(s): "964903316"

Test #3:

score: 0
Accepted
time: 1ms
memory: 3920kb

input:

26 1 26

output:

955348527

result:

ok 1 number(s): "955348527"

Test #4:

score: 0
Accepted
time: 1ms
memory: 4076kb

input:

40 11 33

output:

695661890

result:

ok 1 number(s): "695661890"

Test #5:

score: 0
Accepted
time: 1ms
memory: 4024kb

input:

39 39 38

output:

717149364

result:

ok 1 number(s): "717149364"

Test #6:

score: 0
Accepted
time: 1ms
memory: 3916kb

input:

40 10 25

output:

912929610

result:

ok 1 number(s): "912929610"

Test #7:

score: 0
Accepted
time: 1ms
memory: 3972kb

input:

37 25 23

output:

250748685

result:

ok 1 number(s): "250748685"

Test #8:

score: 0
Accepted
time: 1ms
memory: 3964kb

input:

39 2 38

output:

624060592

result:

ok 1 number(s): "624060592"

Test #9:

score: 0
Accepted
time: 1ms
memory: 3920kb

input:

40 18 22

output:

739993796

result:

ok 1 number(s): "739993796"

Test #10:

score: 0
Accepted
time: 1ms
memory: 4028kb

input:

40 11 35


output:

135213497

result:

ok 1 number(s): "135213497"

Subtask #3:

score: 15
Accepted

Dependency #1:

100%
Accepted

Dependency #2:

100%
Accepted

Test #11:

score: 15
Accepted
time: 0ms
memory: 4736kb

input:

199 100 70

output:

914653136

result:

ok 1 number(s): "914653136"

Test #12:

score: 0
Accepted
time: 1ms
memory: 4648kb

input:

187 3 40

output:

928785584

result:

ok 1 number(s): "928785584"

Test #13:

score: 0
Accepted
time: 0ms
memory: 4844kb

input:

199 198 197

output:

38412688

result:

ok 1 number(s): "38412688"

Test #14:

score: 0
Accepted
time: 1ms
memory: 4836kb

input:

200 40 140

output:

367088143

result:

ok 1 number(s): "367088143"

Test #15:

score: 0
Accepted
time: 1ms
memory: 4888kb

input:

199 111 3

output:

870834793

result:

ok 1 number(s): "870834793"

Test #16:

score: 0
Accepted
time: 1ms
memory: 4752kb

input:

200 133 73

output:

343127012

result:

ok 1 number(s): "343127012"

Test #17:

score: 0
Accepted
time: 1ms
memory: 4656kb

input:

178 15 163

output:

160852284

result:

ok 1 number(s): "160852284"

Test #18:

score: 0
Accepted
time: 1ms
memory: 4740kb

input:

197 43 79

output:

332057544

result:

ok 1 number(s): "332057544"

Test #19:

score: 0
Accepted
time: 1ms
memory: 4704kb

input:

200 33 79

output:

742545318

result:

ok 1 number(s): "742545318"

Subtask #4:

score: 49
Accepted

Dependency #1:

100%
Accepted

Dependency #2:

100%
Accepted

Dependency #3:

100%
Accepted

Test #20:

score: 49
Accepted
time: 5ms
memory: 8132kb

input:

658 169 438

output:

206087110

result:

ok 1 number(s): "206087110"

Test #21:

score: 0
Accepted
time: 5ms
memory: 8472kb

input:

700 207 509

output:

478311263

result:

ok 1 number(s): "478311263"

Test #22:

score: 0
Accepted
time: 6ms
memory: 9036kb

input:

755 139 507

output:

103783948

result:

ok 1 number(s): "103783948"

Test #23:

score: 0
Accepted
time: 26ms
memory: 26568kb

input:

2000 500 1500

output:

123410309

result:

ok 1 number(s): "123410309"

Test #24:

score: 0
Accepted
time: 21ms
memory: 26524kb

input:

2000 1000 1001

output:

956197482

result:

ok 1 number(s): "956197482"

Test #25:

score: 0
Accepted
time: 19ms
memory: 26564kb

input:

2000 666 1333

output:

993781645

result:

ok 1 number(s): "993781645"

Test #26:

score: 0
Accepted
time: 19ms
memory: 26392kb

input:

1991 198 677

output:

155058730

result:

ok 1 number(s): "155058730"

Test #27:

score: 0
Accepted
time: 7ms
memory: 18532kb

input:

1498 299 659

output:

665757882

result:

ok 1 number(s): "665757882"