骞朵笉瀵瑰姴鐨刲oj3124:uoj477:p5405:[CTS2019]姘噾鎵嬫父
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#include<algorithm>
#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<iomanip>
#include<iostream>
#include<map>
#include<queue>
#include<set>
#include<stack>
#include<vector>
#define rep(i,x,y) for(register int i=(x);i<=(y);++i)
#define dwn(i,x,y) for(register int i=(x);i>=(y);--i)
#define view(u,k) for(int k=fir[u];~k;k=nxt[k])
#define maxn 1007
#define maxsiz 3007
#define LL long long
using namespace std;
int read()
{
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)&&ch!=鈥?鈥?ch=getchar();
if(ch==鈥?鈥?f=-1,ch=getchar();
while(isdigit(ch))x=(x<<1)+(x<<3)+ch-鈥?鈥?ch=getchar();
return x*f;
}
void write(int x)
{
if(x==0){putchar(鈥?鈥?,putchar(鈥榎n鈥?;return;}
int f=0;char ch[20];
if(x<0)putchar(鈥?鈥?,x=-x;
while(x)ch[++f]=x%10+鈥?鈥?x/=10;
while(f)putchar(ch[f--]);
putchar(鈥榎n鈥?;
return;
}
const int mod=998244353;
int n,dp[maxn][maxsiz],siz[maxn],fir[maxn],v[maxn<<1],nxt[maxn<<1],cnte,p[maxn][4],ans,tmp[maxsiz],inv[maxsiz];
int getd(int k){return k<(k^1)?1:0;}
void ade(int u1,int v1){v[cnte]=v1,nxt[cnte]=fir[u1],fir[u1]=cnte++;}
int mo(int x){if(x<0)return x+mod;return x>=mod?x-mod:x;}
int mul(int x,int y){int res=1;while(y){if(y&1)res=(LL)res*x%mod;x=(LL)x*x%mod,y>>=1;}return res;}
void getdp(int u,int fa)
{
rep(i,1,3)dp[u][i]=(LL)i*p[u][i]%mod;siz[u]=1;
view(u,k)if(v[k]!=fa)
{
getdp(v[k],u);
if(getd(k))
{
int li1=siz[u]*3,li2=siz[v[k]]*3;
rep(i,1,li1+li2)tmp[i]=0;
rep(i,1,li1)rep(j,1,li2)
{
tmp[i+j]=mo(tmp[i+j]+(LL)dp[u][i]*dp[v[k]][j]%mod);
}
}
else
{
int li1=siz[u]*3,li2=siz[v[k]]*3;
rep(i,1,li1+li2)tmp[i]=0;
rep(i,1,li1)rep(j,1,li2)tmp[i+j]=mo(tmp[i+j]+(LL)dp[u][i]*mo(-dp[v[k]][j])%mod);
rep(i,1,li1)rep(j,1,li2)tmp[i]=mo(tmp[i]+(LL)dp[u][i]*dp[v[k]][j]%mod);
}
siz[u]+=siz[v[k]];int li=siz[u]*3;
rep(i,1,li)dp[u][i]=tmp[i];
}
int li=siz[u]*3;
rep(i,1,li)dp[u][i]=(LL)dp[u][i]*inv[i]%mod;
}
int main()
{
n=read();int li=n+n+n;
rep(i,1,li)inv[i]=mul(i,mod-2);
rep(i,1,n)
{
p[i][1]=read(),p[i][2]=read(),p[i][3]=read(),fir[i]=-1;
int invp=mo(p[i][1]+mo(p[i][2]+p[i][3]));invp=mul(invp,mod-2);
p[i][1]=(LL)p[i][1]*invp%mod,p[i][2]=(LL)p[i][2]*invp%mod,p[i][3]=(LL)p[i][3]*invp%mod;
}
rep(i,2,n){int x=read(),y=read();ade(x,y),ade(y,x);}
getdp(1,0);li=siz[1]*3;rep(i,0,li)ans=mo(ans+dp[1][i]);
write(ans);
return 0;
}
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