奢侈的旅行(2018-女生赛)(Dijstra+堆优化)

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=6290

Dijstra+堆优化基本操作:https://blog.csdn.net/CSDNjiangshan/article/details/79345031

官方题解:


主要参考博客:https://blog.csdn.net/lzc504603913/article/details/80524386

贴上代码:

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int Maxm=2e5+500;
const int Maxn=1e5+500;
inline void read(int &t){
    char c;
    t=0;
    while((c=getchar())<'0'||c>'9');
    while(c>='0'&&c<='9'){
        t=t*10+(c-'0'),
        c=getchar();
    }
}
struct edge{
    int u,v,a,b,next;
}e[Maxm];
int cnt,head[Maxn];
void add_edge(int u,int v,int a,int b){
    e[cnt].u=u;
    e[cnt].v=v;
    e[cnt].a=a;
    e[cnt].b=b;
    e[cnt].next=head[u];
    head[u]=cnt++;
}
struct Node{
    int id;
    ll d;
    Node(int id,ll d):id(id),d(d){}
    bool operator <(const Node &A)const{
        return d>A.d;
    }
};
ll d[Maxn];
bool vis[Maxn];
int dijstra(int S,int E){
    memset(d,0x3f,sizeof(d));
    memset(vis,0,sizeof(vis));
    priority_queue <Node> que;
    que.push(Node (S,1));
    d[S]=1;
    while(!que.empty()){
        Node tp1=que.top();
        que.pop();
        int tp=tp1.id;
        if(tp==E){
            for(int i=1;;i++){
                if((1LL<<i)>tp1.d){
                    return i-1;
                }
            }
        }
        if(vis[tp])
            continue;
        vis[tp]=1;
        for(int i=head[tp];i!=-1;i=e[i].next){
            if(vis[e[i].v])
                continue;
            if(((e[i].a+tp1.d)/tp1.d)>=(1LL<<e[i].b)&&e[i].a+tp1.d<d[e[i].v]){

                d[e[i].v]=e[i].a+tp1.d;
                que.push(Node(e[i].v,d[e[i].v]));

            }
        }
    }
    return -1;
}
int main()
{
    int T;
    read(T);
    while(T--){
        memset(head,-1,sizeof(head));
        cnt=0;
        int u,v,a,b,N,M;
        read(N),read(M);
        for(int i=0;i<M;i++){
            read(u),read(v),read(a),read(b);
            add_edge(u,v,a,b);
        }
        printf("%d\n",dijstra(1,N));
    }
    return 0;
}

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转载自blog.csdn.net/z_sea/article/details/80709871