I don't want to do the problem, so the portal
is solved
The complexity of memorized search is really metaphysical. 2333
f[i][j][k] means that there are j railways and k roads on the ith city.
Blind search
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<cmath>
using namespace std;
typedef long long LL;
inline int read()
{
int f=1,x=0;char ch=getchar();
while(ch<'0' || ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0' && ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
inline LL readx()
{
LL f=1,x=0;char ch=getchar();
while(ch<'0' || ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0' && ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
LL f[21000][45][45],ans;
int s[21000],t[21000];
LL C[21000],A[21000],B[21000];
LL dfs(int x,int u,int v)//公 铁
{
if(x<0)return C[abs(x)]*(A[abs(x)]+u)*(B[abs(x)]+v);
if(f[x][u][v]!=-1)return f[x][u][v];
LL cnt=0;
cnt+=dfs(s[x],u,v);//翻修公路
cnt+=dfs(t[x],u,v+1);
f[x][u][v]=cnt;cnt=0;
cnt+=dfs(t[x],u,v);
cnt+=dfs(s[x],u+1,v);
f[x][u][v]=min(f[x][u][v],cnt);
return f[x][u][v];
}
int n;
int main()
{
//freopen("road.in","r",stdin);
// freopen("road.out","w",stdout);
n=read();
for(int i=1;i<n;i++)s[i]=read(),t[i]=read();
for(int i=1;i<=n;i++)A[i]=readx(),B[i]=readx(),C[i]=readx();
memset(f,-1,sizeof(f));
dfs(1,0,0);
printf("%lld\n",f[1][0][0]);
return 0;
}