dijkstra

#define pa pair<int,int>
int n,m,tot;
int d[1005],head[1005];
bool v[1005];
struct edge{int go,next,w;}e[50005];
void insert(int x,int y,int z)
{
    e[++tot].go=y;e[tot].w=z;e[tot].next=head[x];head[x]=tot;
}
void dijkstra()
{
    priority_queue<pa,vector<pa>,greater<pa> >q;
    for(int i=1;i<=n;i++)d[i]=inf;
    memset(v,0,sizeof(v));
    d[1]=0;q.push(make_pair(0,1));
    while(!q.empty())
    {
        int x=q.top().second;q.pop();
        if(v[x])continue;v[x]=1;
        for(int i=head[x],y;i;i=e[i].next)
            if(d[x]+e[i].w<d[y=e[i].go])
            {
                d[y]=d[x]+e[i].w;
                q.push(make_pair(d[y],y));
            }
        
    }
}