【模板】堆优化的dijkstra

生命算法，以防忘记

#include<bits/stdc++.h>
using namespace std;
int head[200005],dis[200005],n,m,s,f,g,w,l;
bool sign[200005];
struct node
{
	int to,next,val;
} a[200005];
inline void in(int from,int to,int v)
{
	a[++l].next=head[from];
	a[l].to=to;
	a[l].val=v;
	head[from]=l;
}
priority_queue < pair<int,int> >q;
inline void dijkstra()
{
	for(register int i=1; i<=n; i++)
		dis[i]=2147483647;
	dis[s]=0;
	q.push(make_pair(0,s));
	while(q.size())
	{
		int x=q.top().second;
		q.pop();
		if(sign[x])continue;
		sign[x]=1;
		for(register int i=head[x]; i; i=a[i].next)
			if(dis[a[i].to]>dis[x]+a[i].val)
			{
				dis[a[i].to]=dis[x]+a[i].val;
				q.push(make_pair(-dis[a[i].to],a[i].to));
			}
	}
}
int main()
{
	scanf("%d%d%d",&n,&m,&s);
	for(register int i=1; i<=m; i++)
	{
		scanf("%d%d%d",&f,&g,&w);
		in(f,g,w);
	}
	dijkstra();
	for(register int i=1; i<=n; i++)
		printf("%d ",dis[i]);
	return 0;
}