最短路 Dijkstra+堆优化

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<queue>
#include<vector>
using namespace std;
int n,m,s,t,cnt,head[100001];
int dis[100001],vis[100001];
struct uio{
    int to,nxt,wei;
}edge[10000001];
struct cmp{
    bool operator () (int x,int y)
    {return dis[x]>dis[y];};
};
priority_queue<int,vector<int>,cmp> que;
void add(int x,int y,int z)
{
    edge[++cnt].nxt=head[x];
    edge[cnt].to=y;
    edge[cnt].wei=z;
    head[x]=cnt;
}
void dijkstra()
{
    memset(dis,0x3f,sizeof(dis));
    dis[s]=0;
    que.push(s);
    while(!que.empty())
    {
        int x=que.top();
        que.pop();
        if(!vis[x])
        {
            vis[x]=1;
            for(int i=head[x];i;i=edge[i].nxt)
            {
                int y=edge[i].to;
                dis[y]=min(dis[y],dis[x]+edge[i].wei);
                que.push(y);
            }
        }
    }
}
int main()
{
    scanf("%d%d%d%d",&n,&m,&s,&t);
    for(int i=1;i<=m;i++)
    {
        int u,v,w;
        scanf("%d%d%d",&u,&v,&w);
        add(u,v,w);
    }
    dijkstra();
    return 0;
}

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转载自www.cnblogs.com/water-radish/p/9280682.html