PAT甲级 All Roads Lead to Rome (30)

#include<bits/stdc++.h>
using namespace std;

#define debug puts("YES");
#define rep(x,y,z) for(int (x)=(y);(x)<(z);(x)++)
#define ll long long

#define lrt int l,int r,int rt
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define root l,r,rt
#define mst(a,b) memset((a),(b),sizeof(a))
#define pii pair<int,int>
#define piii pair<int,pii>
#define fi first                                  
#define se second
#define mk(x,y) make_pair(x,y)
const int mod=1e9+7;
const int maxn=5e2+10;
const int ub=1e6;
ll powmod(ll x,ll y){ll t; for(t=1;y;y>>=1,x=x*x%mod) if(y&1) t=t*x%mod; return t;}
ll gcd(ll x,ll y){
    if(y==0) return x;
    return gcd(y,x%y);
}
string s,t;
int n,m,tot=0,ft;
vector<pii> g[maxn];
map<string,int> mp;
map<int,string> mp2;
piii d[maxn];
struct node{
    int x;
    bool operator<(const node& y) const{
        return d[x]>d[y.x];
    }
};
vector<int> ans;
int h[maxn],nxt[maxn];
piii add(piii x,piii y){
    return mk(x.fi+y.fi,mk(x.se.fi+y.se.fi,x.se.se+y.se.se));
}
void bfs(int S){
    piii tpp=mk(mod,mk(0,mod));
    rep(i,0,maxn) d[i]=tpp;
    d[S]=mk(0,mk(0,0));
    nxt[S]=-1;
    priority_queue<node> pq;pq.push(node{S});
    while(!pq.empty()){
        node tpp=pq.top();pq.pop();
        int tp=tpp.x;
        if(tp==ft) break;
        rep(i,0,g[tp].size()){
            int v=g[tp][i].fi,w=g[tp][i].se;
            piii ad=mk(w,mk(-h[v],1));
            if(add(d[tp],ad)<=d[v]){
                d[v]=add(d[tp],ad);
                nxt[v]=tp;
                pq.push(node{v});
            }
        }
    }
    int tmp=ft;
    while(nxt[tmp]!=-1){
        ans.push_back(tmp);
        tmp=nxt[tmp];
    }
}
int cnt[maxn];
int dfs(int u,int x){
    if(x>d[u].fi) return 0;
    if(cnt[u]) return cnt[u];
    int ret=0;
    rep(i,0,g[u].size()){
        int v=g[u][i].fi,w=g[u][i].se;
        ret+=dfs(v,x+w);
    }
    return cnt[u]=ret;
}
int main(){
    ios::sync_with_stdio(false);
    cin>>n>>m>>s;
    mp2[tot]=s,mp[s]=tot++;
    rep(i,1,n){
        int x;
        cin>>s>>x;
        if(s=="ROM") ft=tot;
        h[tot]=x,mp2[tot]=s,mp[s]=tot++;
    }
    rep(i,0,m){
        int v;
        cin>>s>>t>>v;
        int x=mp[s],y=mp[t];
        g[x].push_back(mk(y,v));
        g[y].push_back(mk(x,v));
    }
    bfs(0);cnt[ft]=1;
    int ret=dfs(0,0);
    cout<<ret<<" "<<d[ft].fi<<" "<<-d[ft].se.fi<<" "<<-d[ft].se.fi/d[ft].se.se<<"\n";
    int sz=ans.size();
    cout<<mp2[0];
    for(int i=sz-1;i>=0;i--){
        cout<<"->"<<mp2[ans[i]];
    }
    cout<<"\n";
    return 0;
}