QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#676733#8339. Rooted TreeItzDesertAC ✓253ms316216kbC++171.5kb2024-10-25 23:47:052024-10-25 23:47:05

Judging History

你现在查看的是最新测评结果

  • [2024-10-25 23:47:05]
  • 评测
  • 测评结果:AC
  • 用时:253ms
  • 内存:316216kb
  • [2024-10-25 23:47:05]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const ll p = 1e9+9;
ll qpow(ll a,ll n)
{
    ll ans = 1;
    while(n)
    {
        if(n&1) ans = (ans*a)%p;
        a = (a*a)%p;
        n>>=1;
    }
    return ans;
}
const int maxn = 1e7+5;
ll s[maxn],sv[maxn],inv[maxn];
ll E2[maxn];
void mod(ll & x)
{
    if(x>=p) x-=p;
    else if(x<0) x+=p;
}
//(m-1)(x-1)+1 for x = 1 到 k.
void init(int m,int k)
{
    s[0] = 1;
    for(int i = 1;i<=k;i++)
    {
        ll curval = 1ll*(m-1)*(i-1)+1;
        s[i] = (s[i-1]*curval)%p;
    }
    sv[k] = qpow(s[k],p-2);
    for(int i = k;i>=1;i--)
    {
        ll curval = 1ll*(m-1)*(i-1)+1;
        sv[i-1] = (sv[i]*curval)%p;
    }
    for(int i = 1;i<=k;i++) inv[i] = (sv[i]*s[i-1])%p;
    //i次操作后的叶子深度和期望   
    E2[0] = 0;
    for(int i = 1;i<=k;i++)
    {
        E2[i] = (1ll*(m-1)*i+1)*inv[i]%p*E2[i-1]%p;
        E2[i]+=m;
        mod(E2[i]);
    }
    ll ans = 0;
    //每次操作的贡献:上一次操作后的叶子深度和预期 / 叶子数目 = avg深度
    for(int i = 1;i<=k;i++)
    {
        ll del = E2[i-1]*inv[i]%p;
        del++;mod(del);
        del = (del*m)%p;
        ans+=del;
        mod(ans);
    }
    cout<<ans<<'\n';
}
void solve()
{    
    
    int m,k;cin>>m>>k;
    init(m,k);
    for(int i = 1;i<=k;i++)
    {

    }
}

int main(){
    ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int T = 1;
    //cin>>T;
    while (T--)
    {
        solve();
    }   
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 9852kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

score: 0
Accepted
time: 1ms
memory: 9808kb

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 16ms
memory: 31440kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: 0
Accepted
time: 160ms
memory: 218696kb

input:

48 6713156

output:

198541581

result:

ok 1 number(s): "198541581"

Test #5:

score: 0
Accepted
time: 1ms
memory: 9788kb

input:

1 111

output:

6216

result:

ok 1 number(s): "6216"

Test #6:

score: 0
Accepted
time: 184ms
memory: 240352kb

input:

28 7304152

output:

457266679

result:

ok 1 number(s): "457266679"

Test #7:

score: 0
Accepted
time: 100ms
memory: 142044kb

input:

38 4101162

output:

232117382

result:

ok 1 number(s): "232117382"

Test #8:

score: 0
Accepted
time: 246ms
memory: 315472kb

input:

51 9921154

output:

340670552

result:

ok 1 number(s): "340670552"

Test #9:

score: 0
Accepted
time: 40ms
memory: 68460kb

input:

79 1801157

output:

620550406

result:

ok 1 number(s): "620550406"

Test #10:

score: 0
Accepted
time: 137ms
memory: 177804kb

input:

22 5417157

output:

457449071

result:

ok 1 number(s): "457449071"

Test #11:

score: 0
Accepted
time: 93ms
memory: 110976kb

input:

25 3210162

output:

36368303

result:

ok 1 number(s): "36368303"

Test #12:

score: 0
Accepted
time: 76ms
memory: 101376kb

input:

67 2919160

output:

935195555

result:

ok 1 number(s): "935195555"

Test #13:

score: 0
Accepted
time: 220ms
memory: 278864kb

input:

77 8613163

output:

482832472

result:

ok 1 number(s): "482832472"

Test #14:

score: 0
Accepted
time: 241ms
memory: 316216kb

input:

90 10000000

output:

275581651

result:

ok 1 number(s): "275581651"

Test #15:

score: 0
Accepted
time: 253ms
memory: 316140kb

input:

99 9999999

output:

126087169

result:

ok 1 number(s): "126087169"

Test #16:

score: 0
Accepted
time: 244ms
memory: 316164kb

input:

100 10000000

output:

451590067

result:

ok 1 number(s): "451590067"

Extra Test:

score: 0
Extra Test Passed