#include<cstdio>
#include<queue>
#include<cstring>
#include<iostream>
using namespace std;
typedef long long ll;
const ll INF=10000000000;
const int M=1000020;
class Edge
{
public:
ll v,next,w;
};
Edge edges[M];
int head[M],cnt;
ll d[M];
int n;
ll u[M],v[M],w[M];
struct HeapNode
{
ll d,u;
bool operator < (const HeapNode& rhs)const
{
return d>rhs.d;
}
};
priority_queue<HeapNode>Q;
bool done[M]= {0};
void init()
{
memset(done,0,sizeof(done));
memset(head, -1, sizeof(head));
while(!Q.empty())
Q.pop();
cnt=0;
}
void addedge(int u,int v,int w)
{
edges[cnt].v=v;
edges[cnt].w=w;
edges[cnt].next=head[u];
head[u]=cnt++;
}
int main()//DJ
{
int t;
scanf("%d",&t);
while(t)
{
t--;
init();
scanf("%d",&n);
int m;
scanf("%d",&m);
for(int i=0; i<m; i++)
{
scanf("%I64d%I64d%I64d",&u[i],&v[i],&w[i]);
addedge(u[i],v[i],w[i]);
}
int s=1;
for(int i=1; i<=n; i++)
d[i]=INF;
d[s]=0;
Q.push(HeapNode{0,s});
while(!Q.empty())
{
HeapNode x=Q.top();
Q.pop();
int u=x.u;
if(done[u])
continue;
done[u]=1;
for(int i=head[u]; i!=-1; i=edges[i].next)
{
Edge&e=edges[i];
if(d[e.v]>d[u]+e.w)
{
d[e.v]=d[u]+e.w;
Q.push(HeapNode{d[e.v],e.v});
}
}
}
}
}
【最短路】【模板】Dijstra 优先队列优化
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转载自blog.csdn.net/qq_32259423/article/details/81356828
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