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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
#646920#8339. Rooted TreeXiaoMo247AC ✓232ms316200kbC++171.1kb2024-10-17 09:57:232024-10-17 09:57:24

Judging History

你现在查看的是最新测评结果

  • [2024-10-17 09:57:24]
  • 评测
  • 测评结果:AC
  • 用时:232ms
  • 内存:316200kb
  • [2024-10-17 09:57:23]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll MOD = 1e9 + 9;
const ll MAXN = 1e7 + 5;
ll m, k, E[MAXN], f[MAXN], invf[MAXN], inv[MAXN];
ll fastPow(ll a, ll b){
    ll ret = 1;
    while(b){
        if(b & 1) ret = ret * a % MOD;
        a = a * a % MOD;
        b >>= 1;
    }
    return ret;
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    cin >> m >> k;
    ll ans = 0;
    f[0] = 1;
    for(int i = 1; i <= k; i ++){
        f[i] = f[i - 1] * ((i * (m - 1) + 1) % MOD) % MOD;
    }
    invf[k] = fastPow(f[k], MOD - 2);
    for(int i = k - 1; i >= 1; i --){
        invf[i] = invf[i + 1] * ((i + 1) * (m - 1) + 1) % MOD;
    }
    inv[0] = invf[0] = 1;
    for(int i = 1; i <= k; i ++){
        inv[i] = invf[i] * f[i - 1] % MOD;
    }
    for(int i = 1; i <= k; i ++){
        E[i] = (E[i - 1] * inv[i - 1] % MOD * ((i * (m - 1) + 1) % MOD) % MOD + m) % MOD;
        ans = (ans + (i == k ? E[i] : E[i] * inv[i])) % MOD;
        // cout << E[i] << "\n";
    }
    cout << ans << "\n";
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 7752kb

input:

6 2

output:

18

result:

ok 1 number(s): "18"

Test #2:

score: 0
Accepted
time: 1ms
memory: 7692kb

input:

2 6

output:

600000038

result:

ok 1 number(s): "600000038"

Test #3:

score: 0
Accepted
time: 12ms
memory: 26720kb

input:

83 613210

output:

424200026

result:

ok 1 number(s): "424200026"

Test #4:

score: 0
Accepted
time: 143ms
memory: 218972kb

input:

48 6713156

output:

198541581

result:

ok 1 number(s): "198541581"

Test #5:

score: 0
Accepted
time: 1ms
memory: 7692kb

input:

1 111

output:

6216

result:

ok 1 number(s): "6216"

Test #6:

score: 0
Accepted
time: 158ms
memory: 239288kb

input:

28 7304152

output:

457266679

result:

ok 1 number(s): "457266679"

Test #7:

score: 0
Accepted
time: 90ms
memory: 138872kb

input:

38 4101162

output:

232117382

result:

ok 1 number(s): "232117382"

Test #8:

score: 0
Accepted
time: 209ms
memory: 315284kb

input:

51 9921154

output:

340670552

result:

ok 1 number(s): "340670552"

Test #9:

score: 0
Accepted
time: 41ms
memory: 67532kb

input:

79 1801157

output:

620550406

result:

ok 1 number(s): "620550406"

Test #10:

score: 0
Accepted
time: 116ms
memory: 177112kb

input:

22 5417157

output:

457449071

result:

ok 1 number(s): "457449071"

Test #11:

score: 0
Accepted
time: 72ms
memory: 108072kb

input:

25 3210162

output:

36368303

result:

ok 1 number(s): "36368303"

Test #12:

score: 0
Accepted
time: 66ms
memory: 102352kb

input:

67 2919160

output:

935195555

result:

ok 1 number(s): "935195555"

Test #13:

score: 0
Accepted
time: 198ms
memory: 278480kb

input:

77 8613163

output:

482832472

result:

ok 1 number(s): "482832472"

Test #14:

score: 0
Accepted
time: 225ms
memory: 316200kb

input:

90 10000000

output:

275581651

result:

ok 1 number(s): "275581651"

Test #15:

score: 0
Accepted
time: 217ms
memory: 316080kb

input:

99 9999999

output:

126087169

result:

ok 1 number(s): "126087169"

Test #16:

score: 0
Accepted
time: 232ms
memory: 316156kb

input:

100 10000000

output:

451590067

result:

ok 1 number(s): "451590067"

Extra Test:

score: 0
Extra Test Passed