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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#768817#9553. The HermitSuhy#WA 12ms6660kbC++231.4kb2024-11-21 14:40:312024-11-21 14:40:31

Judging History

你现在查看的是最新测评结果

  • [2024-11-21 14:40:31]
  • 评测
  • 测评结果:WA
  • 用时:12ms
  • 内存:6660kb
  • [2024-11-21 14:40:31]
  • 提交

answer

#include<cstdio>
typedef unsigned long long u64;
const int M=998244353;
int n,m,i,j,k;
int s,p[10086],l[100086],D[100086];
bool b[100086];
u64 F[100086],G[100086];
u64 *f[100086];
int d[100086];
u64 ans;
u64 pow(u64 u,u64 d){
    if(!u)return 1;
    u64 r=pow(u>>1,d);
    r*=r;
    if(u&1)(r%=M)*=d;
    return r%M;
}
u64 C(int n,int m){
    if(n<m)return 0;
    return F[n]*G[m]%M*G[n-m]%M;
}
int main(){
    scanf("%d%d",&n,&m);
    F[0]=1;
    for(i=1;i<=n;++i)F[i]=F[i-1]*i%M;
    G[n]=pow(M-2,F[n]);
    for(i=n;i;--i)G[i-1]=G[i]*i%M;
    for(i=2;i<=n;++i){
        if(!b[i])p[s++]=i,l[i]=i;
        for(j=0;j<s&&p[j]<=i&&(k=i*p[j],k<=n);++j)
            b[k]=1,l[k]=p[j];
    }
    D[1]=1;
    for(i=2;i<=n;++i){
        j=1;
        D[i]=1;
        for(int t=i;t>1;){
            if(l[t]!=k)D[i]*=j,k=l[t],j=1;
            t/=l[t],++j;
        }
        D[i]*=j;
    }
    for(i=1;i<=n;++i)if(d[n/i]<D[i])d[n/i]=D[i];
    for(i=1;i<=n;++i)if(d[i]){
        f[i]=new u64[d[i]+1];
        for(j=0;j<=d[i]&&j<m;++j){
            f[i][j]=C(i,m-j);
            for(k=2;k<=i&&i/k>=m-j;++k){
                (f[i][j]+=M-f[i/k][j])%=M;
                // if(d[i/k]<j)puts("A");
            }
        }
    }
    for(i=1;i<=n;++i)
    for(j=0;j<=D[i]&&j<m;++j){
        u64 u=f[n/i][j]+C(n/i-1,m-j)+M-C(n/i,m-j);
        ans+=C(D[i],j)*u%M*(m-j)%M;
    }
    printf("%llu",ans%M);
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 1ms
memory: 5788kb

input:

4 3

output:

7

result:

ok 1 number(s): "7"

Test #2:

score: 0
Accepted
time: 1ms
memory: 5836kb

input:

11 4

output:

1187

result:

ok 1 number(s): "1187"

Test #3:

score: 0
Accepted
time: 12ms
memory: 6444kb

input:

100000 99999

output:

17356471

result:

ok 1 number(s): "17356471"

Test #4:

score: 0
Accepted
time: 2ms
memory: 6212kb

input:

11451 1919

output:

845616153

result:

ok 1 number(s): "845616153"

Test #5:

score: -100
Wrong Answer
time: 4ms
memory: 6660kb

input:

99998 12345

output:

525061036

result:

wrong answer 1st numbers differ - expected: '936396560', found: '525061036'