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The 2nd Universal Cup Finals is coming! Check out our event page, schedule, and competition rules!
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 |
---|---|---|---|---|---|---|---|---|---|
#766391 | #9566. Topology | Stelor | WA | 27ms | 223020kb | C++20 | 2.8kb | 2024-11-20 17:10:56 | 2024-11-20 17:11:05 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
using ll=long long;
const int mod=998244353;
const int N=5010;
int n,sz[N];
ll C[N][N],dp[N][N],pre[N][N],fac[N],f[N],prod[N];
vector<int> v[N];
bool vis[N];
ll qui(ll a,ll b, ll c){
ll ret=1;
while(b){
if(b&1) ret=ret*a%c;
a=a*a%c;
b>>=1;
}
return ret;
}
ll inv(ll a){
return qui(a,mod-2,mod);
}
void init()
{
fac[0]=1;
for(int i=1;i<N;++i) fac[i]=fac[i-1]*i%mod;
C[0][0]=1;
for(int i=1;i<N;++i)
{
for(int j=0;j<N;++j)
{
if(!j) C[i][0]=1;
if(j>i) break;
C[i][j]=(C[i-1][j]+C[i-1][j-1])%mod;
}
}
}
void initDfs(int u,int fa){
sz[u]=1;
for(auto j:v[u]){
if(j==fa) continue;
initDfs(j,u);
sz[u]+=sz[j];
}
}
void initDfs2(int u,int fa){
ll tmp=1;
f[u]=1;
for(auto j:v[u]){
if(j==fa) continue;
tmp=tmp*fac[sz[j]]%mod;
}
f[u]=f[u]*fac[sz[u]-1]%mod*inv(tmp)%mod;
for(auto j:v[u]){
if(j==fa) continue;
initDfs2(j,u);
f[u]=f[u]*f[j]%mod;
}
}
void initDfs3(int u,int fa){
prod[u]=sz[u];
for(auto j:v[u]){
if(j==fa) continue;
initDfs3(j,u);
}
for(auto j:v[u]){
if(j==fa) continue;
prod[u]=prod[u]*prod[j]%mod;
}
}
void dfs(int fa,int lll){
vis[fa]=true;
for(auto u:v[fa]){
if(vis[u]) continue;
vector<ll> pre(n+1);
for(int i=1;i<=n;++i){
if(n-i-sz[u]>=0&&sz[fa]-sz[u]-1>=0)
pre[i]=dp[fa][i]*C[n-i-sz[u]][sz[fa]-sz[u]-1]%mod;
}
for(int i=1;i<=n;++i){
pre[i]=pre[i-1]+pre[i];
pre[i]%=mod;
}
ll now=prod[fa]*inv(prod[u])%mod*inv(sz[fa])%mod;
now=fac[sz[fa]-sz[u]-1]*inv(now);
for(int i=1;i<=n;++i){
assert(sz[fa]-sz[u]-1>=0);
dp[u][i]=pre[i-1]*now%mod;
}
/*
for(int i=1;i<=n;++i){
if(n-i-sz[u]>=0&&sz[fa]-sz[u]-1>=0&&sz[fa]-sz[u]-1>=0){
pre[i]=(pre[i-1]+dp[fa][i]*C[n-i-sz[u]][sz[fa]-sz[u]-1]%mod*
fac[sz[fa]-sz[u]-1]%mod*inv(tmp*inv(sz[u])%mod))%mod;
}
}
for(int j=1;j<=n;++j){
dp[u][j]=pre[j-1];
}
*/
dfs(u,fa);
}
}
void solve(){
cin >> n;
for(int i=2;i<=n;++i){
int x;
cin >> x;
v[x].push_back(i);
}
init();
initDfs(1,0);
initDfs2(1,0);
initDfs3(1,0);
dp[1][1]=1;
dfs(1,0);
for(int i=1;i<=n;++i){
ll ans=dp[i][i]*f[i]%mod*C[n-i][sz[i]-1]%mod;
cout<<ans<<" ";
}
}
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}
詳細信息
Test #1:
score: 100
Accepted
time: 21ms
memory: 203812kb
input:
4 1 1 2
output:
3 2 1 2
result:
ok 4 number(s): "3 2 1 2"
Test #2:
score: 0
Accepted
time: 15ms
memory: 205396kb
input:
9 1 1 2 2 3 3 4 5
output:
672 420 180 160 152 108 120 170 210
result:
ok 9 numbers
Test #3:
score: 0
Accepted
time: 12ms
memory: 203648kb
input:
2 1
output:
1 1
result:
ok 2 number(s): "1 1"
Test #4:
score: -100
Wrong Answer
time: 27ms
memory: 223020kb
input:
500 1 2 3 4 5 6 7 7 8 10 8 10 11 4 11 12 12 17 15 13 21 21 22 5 16 9 24 28 28 19 29 27 17 33 23 3 33 27 30 9 25 34 16 26 30 34 46 45 41 14 43 49 43 35 39 37 26 48 52 58 51 56 51 55 19 48 63 36 67 69 54 60 71 61 29 40 32 77 73 55 66 42 77 72 71 69 62 83 46 64 88 39 83 36 89 94 47 98 57 61 38 80 78 88...
output:
331058271 331058271 107893248 201481008 926937757 763859541 479464589 89314705 -19540330 -863328180 336017568 -228635202 210631424 687959472 215678190 494977892 -461520140 -247378664 46696642 406280762 -192556584 -764812552 -634168158 -877811963 -978899990 956938623 -750748733 -711309548 593729292 -...
result:
wrong answer 5th numbers differ - expected: '579367731', found: '926937757'