# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
622905 | inksamurai | Mag (COCI16_mag) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define int ll
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define vec(...) vector<__VA_ARGS__>
#define _3SgiE60 ios::sync_with_stdio(0),cin.tie(0)
typedef long long ll;
using pii=pair<int,int>;
using vi=vector<int>;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}
// e
const int inf=1e13;
pii compare(const pii&l,const pii&r){
return l.fi*r.se<r.fi*l.se?l:r;
}
signed main(){
_3SgiE60;
int n;
cin>>n;
vec(vi) adj(n);
rep(i,n-1){
int u,v;
cin>>u>>v;
u-=1,v-=1;
adj[u].pb(v);
adj[v].pb(u);
}
vi a(n);
rep(i,n){
cin>>a[i];
}
pii pns={inf,1};
vec(vec(pii)) rbts(n);
vi dist(n);
auto dfs=[&](auto self,int v,int par,int num)->void{
dist[v]=num;
vi chs;
for(auto &u:adj[v]){
if(u==par) continue;
chs.pb(u);
self(self,u,v,num+1);
}
// if(a[v]>1){
vec(pii) ps;
{
for(auto &u:chs){
pii p={inf,1};
rep(i,sz(rbts[u])){
int _u=rbts[u][i].se;
int _prod=rbts[u][i].fi;
int _dist=dist[_u]-num;
if(i==0){
p={_prod,_dist};
}else{
p=compare(pii{_prod,_dist},p);
}
}
if(!sz(ps)){
ps.pb(p);
}else{
ps.pb(compare(ps.back(),p));
}
}
}
vec(pii) sp;
{
per(j,sz(chs)){
int u=chs[j];
pii p={inf,1};
rep(i,sz(rbts[u])){
int _u=rbts[u][i].se;
int _prod=rbts[u][i].fi;
int _dist=dist[_u]-num;
if(i==0){
p={_prod,_dist};
}else{
p=compare(pii{_prod,_dist},p);
}
}
if(!sz(sp)){
sp.pb(p);
}else{
sp.pb(compare(sp.back(),p));
}
}
reverse(sp.begin(), sp.end());
}
rep(j,sz(chs)){
int u=chs[j];
rep(i,sz(rbts[u])){
int _u=rbts[u][i].se;
int _prod=rbts[u][i].fi;
int _dist=dist[_u]-num;
pii p={inf,1};
if(j){
p=compare(p,ps[j-1]);
}
if(j+1<sz(chs)){
p=compare(p,sp[j+1]);
}
if(p.fi==0){
cout<<"
asdzxcxzklchxzlvh\n";
exit(0);
}
if(p.fi<inf and p.fi<inf/a[v] and a[v]*_prod<inf/p.fi){
pii now={p.fi*_prod*a[v],_dist+p.se+1};
pns=compare(pns,now);
}
}
}
if(sz(ps)){
pii p=ps.back();
if(p.fi<inf/a[v]){
pns=compare(pns,pii(p.fi*a[v],p.se+1));
}
}
rep(j,sz(chs)){
int u=chs[j];
for(auto p:rbts[u]){
int _u=p.se;
int _prod=p.fi;
if(_prod<inf/a[v]){
rbts[v].pb(pii(_prod*a[v],_u));
}else{
//
}
}
}
// }else{
// rep(j,sz(chs)){
// int u=chs[j];
// for(auto p:rbts[u]){
// int _u=p.se;
// int _prod=p.fi;
// int _dist=dist[_u]-num;
// // print(a[v],_u,_prod);
// rbts[v].pb(pii(_prod,_u));
// pns=compare(pns,pii(_prod,_dist+1));
// }
// }
// }
rbts[v].pb(pii(a[v],v));
pns=compare(pns,pii(a[v],1));
};
dfs(dfs,0,-1,0);
int g=gcd(pns.fi,pns.se);
pns.fi/=g;
pns.se/=g;
cout<<pns.fi<<"/"<<pns.se<<"\n";
// print(pns.fi,pns.se);
}