luogu3371 【模板】單源最短路徑

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<queue> 
#include<algorithm>
#define mx 2147483647
using namespace std;

int n,m,s,cnt,head[10005],vis[10005],dis[10005],t;
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > q;
struct Edge{
    int to,nxt,vl;
}edge[500005];
void add(int u,int v,int w)
{
    cnt++;
    edge[cnt].to=v;
    edge[cnt].vl=w;
    edge[cnt].nxt=head[u];
    head[u]=cnt;
}
void dijkstra()
{
    memset(dis,0x3f3f3f3f,sizeof dis);//forget
    dis[s]=0;//d[s]
    q.push(make_pair(0,s));
    while(!q.empty() && t<n)
    {
        int u=q.top().second;
        q.pop();//寫在continue後面了
        if(vis[u])continue;
        vis[u]=1;
        t++;//write cnt
        for(int i=head[u];i;i=edge[i].nxt)
        {
            int v=edge[i].to;
            if(!vis[v] && edge[i].vl+dis[u]<dis[v])
            {
                dis[v]=edge[i].vl+dis[u]; 
                q.push(make_pair(dis[v],v));
            }
        }
    }
    return;
}
int x,y,w;
int main()
{
    scanf("%d%d%d",&n,&m,&s);
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d%d",&x,&y,&w);
        add(x,y,w);
    }
    dijkstra();
    for(int i=1;i<=n;i++)
    {
        printf("%d ",dis[i]==0x3f3f3f3f?mx:dis[i]);
    }
}