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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 |
---|---|---|---|---|---|---|---|---|---|
#367211 | #5139. DFS Order 2 | Baiyu0123 | RE | 2ms | 6596kb | C++14 | 2.2kb | 2024-03-25 20:18:20 | 2024-03-25 20:18:21 |
Judging History
answer
#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int maxn=505,mod=998244353;
vector<int> ed[maxn];
int d[maxn],siz[maxn],n;
int sum,g[maxn][maxn],G[20][maxn][maxn],Sum[20];
int f[maxn][maxn];
int fac[maxn],inv[maxn];
void lj(int x,int y) {
ed[x].push_back(y);
ed[y].push_back(x);
}
void init_dfs(int fa,int u) {
d[u]=ed[u].size();siz[u]=1;
for (int i=0;i<ed[u].size();i++) {
if (ed[u][i]==fa) {
for (int j=i+1;j<ed[u].size();j++) {
ed[u][j-1]=ed[u][j];
}
d[u]--;
break;
}
}
for (int i=1;i<=d[u];i++) {
int v=ed[u][i-1];
init_dfs(u,v);
siz[u]+=siz[v];
}
}
void add(int &x,int y) {
x=(x+y)%mod;
}
void output(int f[][maxn]) {
for (int i=1;i<=n;i++) {
for (int j=1;j<=n;j++) {
cout<<f[i][j]<<" ";
}
cout<<endl;
}
cout<<endl;
}
void getans(int u,int l,int r) {
for (int i=l;i<=r;i++) {
int v=ed[u][i-1];
for (int p=sum;p>=0;p--) {
for (int j=d[u]-1;j>=0;j--) {
add(g[p+siz[v]][j+1],g[p][j]);
}
}
sum+=siz[v];
}
}
void calc(int u,int l,int r,int dep) {
if (l==r) {
int v=ed[u][l-1];
for (int k=1;k<=n-siz[u]+1;k++) {
for (int p=1;p<=siz[u]-1;p++) {
for (int j=0;j<=d[u]-1;j++) {
add(f[v][k+p],
1ll*f[u][k]*g[p-1][j]%mod*fac[j]%mod*fac[d[u]-j-1]%mod*inv[d[u]]%mod);
}
}
}
return ;
}
int mid=(l+r)>>1;
memcpy(G[dep],g,sizeof(g));Sum[dep]=sum;
getans(u,mid+1,r);
calc(u,l,mid,dep+1);
memcpy(g,G[dep],sizeof(g));sum-Sum[dep];
getans(u,l,mid);
calc(u,mid+1,r,dep+1);
}
void dfs(int fa,int u) {
if (d[u]==0) return;
memset(g,0,sizeof(g));
g[0][0]=1;
calc(u,1,d[u],0);
for (int i=1;i<=d[u];i++) {
int v=ed[u][i-1];
dfs(u,v);
}
}
int qpow(int x,int y) {
ll ret=1,bas=x;
while (y) {
if (y&1) ret=ret*bas%mod;
bas=bas*bas%mod;
y>>=1;
}
return ret;
}
int main() {
ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
cin>>n;
fac[0]=1;
for (int i=1;i<=n;i++) fac[i]=1ll*fac[i-1]*i%mod;
for (int i=0;i<=n;i++) inv[i]=qpow(fac[i],mod-2);
for (int l=2;l<=n;l++) {
int x,y;cin>>x>>y;
lj(x,y);
}
init_dfs(1,1);
f[1][1]=1;
for (int i=1;i<=n;i++) f[1][1]=1ll*f[1][1]*fac[d[i]]%mod;
dfs(1,1);
output(f);
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 5660kb
input:
5 1 2 1 3 3 4 3 5
output:
4 0 0 0 0 0 2 0 0 2 0 2 2 0 0 0 0 1 2 1 0 0 1 2 1
result:
ok 25 numbers
Test #2:
score: 0
Accepted
time: 2ms
memory: 6596kb
input:
10 9 2 9 6 10 5 1 5 1 6 9 3 5 8 4 3 7 9
output:
24 0 0 0 0 0 0 0 0 0 0 0 0 4 2 2 8 2 2 4 0 0 0 4 4 4 4 4 4 0 0 0 0 0 4 4 4 4 4 4 0 12 0 0 0 0 0 12 0 0 0 12 0 0 12 0 0 0 0 0 0 0 0 4 2 2 8 2 2 4 0 0 6 6 0 0 0 0 6 6 0 0 12 0 0 12 0 0 0 0 0 0 6 6 0 0 0 0 6 6
result:
ok 100 numbers
Test #3:
score: -100
Runtime Error
input:
100 18 100 91 87 28 83 11 98 51 52 24 91 72 53 18 19 89 16 77 35 26 25 73 16 96 70 56 44 69 10 63 30 54 95 39 66 58 98 8 71 58 65 74 73 2 64 12 19 32 81 31 54 43 41 84 59 55 75 72 81 59 37 10 94 93 2 64 47 13 32 36 84 28 22 30 28 25 77 47 6 80 52 54 17 23 40 47 88 49 53 65 27 99 59 25 70 91 9 74 1 7...