poj 1511 dijkstra+反向建图+vector(7172ms) dijkstra+反向建图+链式前向星(2266ms)

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//dijkstra,有向图,逆邻接表
//vector容器还是挺费时间的
#include 
#include
#include
#include
#include
using namespace std;
typedef long long LL;
typedef pairPII;
const int maxn=1000010;
const LL INF=1e10+10;
struct Edge{
int to;
LL weight;
Edge(int to,LL weight):to(to),weight(weight) {}
};
vectoredges[maxn];
int u[maxn],pos[maxn];                                  //反向建图
LL cost[maxn];
LL d[maxn];
bool done[maxn];
int v,e;
void dijkstra()
{
    memset(done,false,sizeof(done));
    for(int i=1;i<=v;i++)
        d[i]=(i==1?0:INF);
    priority_queuevector,greater >pq;
    pq.push(PII(d[1],1));
    while(!pq.empty())
    {
        PII k=pq.top();
        pq.pop();
        int v1=k.second;
        if(done[v1]) continue;
        done[v1]=true;
        for(int i=0;iif(d[edges[v1][i].to]>d[v1]+edges[v1][i].weight) {
                d[edges[v1][i].to]=d[v1]+edges[v1][i].weight;
                pq.push(PII(d[edges[v1][i].to],edges[v1][i].to));
            }
    }
}
int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d",&v,&e);
        for(int i=0;iscanf("%d%d%lld",&u[i],&pos[i],&cost[i]);
            edges[u[i]].push_back(Edge(pos[i],cost[i]));
        }
        dijkstra();
        LL sum=0;
        for(int i=1;i<=v;i++)
                {
                    sum+=d[i];
                    edges[i].clear();
                }
        //反向建图
        for(int i=0;ifor(int i=1;i<=v;i++)
        {
            sum+=d[i];
            edges[i].clear();
        }
        printf("%lld\n",sum);
    }
    return 0;
}

//链式前向星+dijkstra
//dijkstra,有向图,逆邻接表
#include 
#include
#include
#include
#include
using namespace std;
typedef long long LL;
typedef pairPII;
const int maxn=1000010;
const LL INF=1e10+10;
struct Edge{
int next,to;
LL weight;
};
Edge edges[maxn];
int head[maxn],cnt;
int u[maxn],pos[maxn];
LL cost[maxn];
LL d[maxn];
bool done[maxn];
int v,e;
void dijkstra()
{
    memset(done,false,sizeof(done));
    for(int i=1;i<=v;i++)
        d[i]=(i==1?0:INF);
    priority_queue,greater >pq;
    pq.push(PII(d[1],1));
    while(!pq.empty())
    {
        PII k=pq.top();
        pq.pop();
        int v1=k.second;
        if(done[v1]) continue;
        done[v1]=true;
        for(int i=head[v1];i!=0;i=edges[i].next)
            if(d[edges[i].to]>d[v1]+edges[i].weight) {
                d[edges[i].to]=d[v1]+edges[i].weight;
                pq.push(PII(d[edges[i].to],edges[i].to));
            }
    }
}
void add(int U,int V,LL c)
{
    edges[++cnt].next=head[U];
    edges[cnt].to=V;
    edges[cnt].weight=c;
    head[U]=cnt;
}
int main()
{
    std::ios::sync_with_stdio(false);
    cin.tie(0);
    int T;
    scanf("%d",&T);
    while(T--)
    {
        memset(head,0,sizeof(head));
        cnt=0;
        scanf("%d%d",&v,&e);
        for(int i=0;i