dij模板

Posted 2021-12-28 shineeternal

#include<cstdio>
#include<vector>
#include<queue>
using namespace std;
struct edge

    int to,val;
;
priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > >q;
vector<edge>e[2505];
int dis[2505];
int vis[2505];
int main()

    int n,m;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++)
    
        int x,y,z; 
        scanf("%d%d%d",&x,&y,&z);
        edge tmp;
        tmp.to=y;
        tmp.val=z;
        e[x].push_back(tmp);
        tmp.to=x;
        tmp.val=z;
        e[y].push_back(tmp);
     
    for(int i=1;i<=n;i++)
    
        dis[i]=2147483647;
    
    dis[1]=0;
    q.push(make_pair(0,1));
    while(!q.empty())
    
        int x=q.top().second;
        q.pop();
        if(vis[x]==1)
        continue;
        vis[x]=1;
        for(int i=0;i<e[x].size();i++)
        
            int y=e[x][i].to;
            if(dis[x]+e[x][i].val<dis[y])
            
                dis[y]=dis[x]+e[x][i].val;
                q.push(make_pair(dis[y],y));
            
        
    
    printf("%d\n",dis[n]);
    return 0;