大陆争~~爸~~霸题解

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<queue>
#include<vector>
#include<climits>
#define int long long
#define maxa 8005

using namespace std;
void read(int &x){
    x=0;
    int f=1;
    char c=getchar();
    while(c<'0'||c>'9'){
        if(c=='-')f=-1;
        c=getchar();
    }
    while(c<='9'&&c>='0'){
        x=((x<<1)+(x<<3))+c-'0';
        c=getchar();
    }
    x*=f;
    return ;
}
int n,m;
int l[maxa];
vector <int> a[maxa];
int to[maxa*20],nxt[maxa*20],h[maxa],top,val[maxa*20];
void psh(int u,int v,int va){
    to[++top]=v,nxt[top]=h[u],h[u]=top,val[top]=va;
    return ;
}

int d1[maxa],d2[maxa],c[maxa];
bool vis[maxa];
void AC_DREAM(){
    priority_queue<pair <int,int> ,vector<pair <int,int> >,greater<pair <int,int> > >q;
    for(int i=1;i<=n;i++)d1[i]=INT_MAX;
    q.push(make_pair(0,1));
    d1[1]=0;
    while(!q.empty()){
        int now=q.top().second;q.pop();
        if(vis[now])continue;
        vis[now]=1;
        int mx=max(d1[now],d2[now]);
        for(int i=h[now];i;i=nxt[i]){
            int y=to[i];
            if(mx+val[i]<d1[y]){
                d1[y]=mx+val[i];
                int tmp=max(d1[y],d2[y]);
                if(!c[y])q.push(make_pair(tmp,y));
            }
        }
        for(int i=0,t;i<l[now];i++){
            t=a[now][i];
            c[t]--;d2[t]=max(d2[t],mx);
            int tmp=max(d1[t],d2[t]);
            if(!c[t])q.push(make_pair(tmp,t));
        }
    }
    return ;
}
#undef int
int main(){
    #define int long long
    read(n),read(m);
    for(int i=1,u,v,va;i<=m;i++){
        read(u),read(v),read(va);
        if(u!=v)psh(u,v,va);
    }
    for(int i=1,x;i<=n;i++){
        read(c[i]);
        for(int j=1;j<=c[i];j++){
            read(x);
            l[x]++;
            a[x].push_back(i);
        }
    }
    AC_DREAM();
    cout<<max(d1[n],d2[n]);
}