天天看点

L3-007 天梯地图 (30分)

L3-007 天梯地图 (30分)
L3-007 天梯地图 (30分)
L3-007 天梯地图 (30分)

想了一晚上,不知道为什么第三个点过不了,希望有大佬能给予帮助

#include<bits/stdc++.h>
using namespace std;
const int maxn=507;
const int maxm=300007;
int n,m;
int s,e;
int cnt,head[maxn];
int vis[maxn],dis[maxn],span[maxn],pred[maxn],pret[maxn],step[maxn];
int ans1[maxn],ans2[maxn],cnt1,cnt2;
struct node
{
    int to;
    int next;
    int cost;
    int time;
}edge[maxm];
void add(int x,int y,int z,int t)
{
    edge[++cnt].to=y;
    edge[cnt].next=head[x];
    edge[cnt].cost=z;
    edge[cnt].time=t;
    head[x]=cnt;
}
void dij(int start)
{
    memset(dis,0x3f,sizeof(dis));
    memset(span,0x3f,sizeof(span));
    memset(step,0x3f,sizeof(step));
    vis[start]=1;
    dis[start]=0;
    span[start]=0;
    step[start]=0;
    for(int i=head[start];i;i=edge[i].next)
    {
        int v=edge[i].to;
        if(dis[v]>dis[start]+edge[i].cost||(dis[v]==dis[start]+edge[i].cost&&step[v]>step[start]+1))
        {
            step[v]=step[start]+1;
            dis[v]=dis[start]+edge[i].cost;
            pred[v]=start;
        }
        if(span[v]>span[start]+edge[i].time||(span[v]==span[start]+edge[i].time&&dis[v]>dis[start]+edge[i].cost))
        {
            span[v]=span[start]+edge[i].time;
            pret[v]=start;
        }
    }
  /*  queue<int>q;
    q.push(start);
    step[start]=0;
    while(!q.empty())
    {
        int u=q.front();
        q.pop();
        vis[u]=0;
        for(int i=head[u];i;i=edge[i].next)
        {
            int v=edge[i].to;
            if(dis[v]>dis[u]+edge[i].cost||(dis[v]==dis[u]+edge[i].cost&&step[v]>step[u]+1))
            {
                step[v]=step[u]+1;
                dis[v]=dis[u]+edge[i].cost;
                pred[v]=u;
                if(!vis[v])
                {
                    q.push(v);
                    vis[v]=1;
                }
            }
        }
    }*/
    while(1)
    {
        int mi=10000000,flag=-1;
        for(int i=1;i<=n;i++)
        {
            if(dis[i]<mi&&!vis[i])
            {
                flag=i;
                mi=dis[i];
            }
        }
        //for(int i=1;i<=n;i++)
      //  printf("i:%d dis:%d\n",i,dis[i]);
        if(flag==-1) break;
        vis[flag]=1;
        for(int i=head[flag];i;i=edge[i].next)
        {
            int v=edge[i].to;
            //printf("flag:%d dis:%d cost:%d pred:%d dis:%d stepflag:%d stepv:%d\n",flag,dis[flag],edge[i].cost,pred[flag],dis[v],step[flag],step[v]);
            if(dis[v]>dis[flag]+edge[i].cost||(dis[v]==dis[flag]+edge[i].cost&&step[v]>step[flag]+1))
            {
                step[v]=step[flag]+1;
                dis[v]=dis[flag]+edge[i].cost;
                pred[v]=flag;
            }
        }
    }
    memset(vis,0,sizeof(vis));
    vis[start]=1;
    while(1)
    {
        int mi=10000000,flag=-1;
        for(int i=1;i<=n;i++)
        {
            if(span[i]<mi&&!vis[i])
            {
                flag=i;
                mi=span[i];
            }
        }
        if(flag==-1) break;
        vis[flag]=1;
        for(int i=head[flag];i;i=edge[i].next)
        {
            int v=edge[i].to;
            if(span[v]>span[flag]+edge[i].time||(span[v]==span[flag]+edge[i].time&&dis[v]>dis[flag]+edge[i].cost))
            {
                span[v]=span[flag]+edge[i].time;
                pret[v]=flag;
            }
        }
    }

}
void print(int cur)
{
    if(cur==0) return ;
    print(pret[cur]);
    ans1[++cnt1]=cur;
    //printf("%d => ",cur);
}
void prind(int cur)
{
    if(cur==0) return;
    prind(pred[cur]);
    ans2[++cnt2]=cur;
    //printf("%d => ",cur);
}
int main()
{
    int a,b,c,d,e;
    scanf("%d%d",&n,&m);
    while(m--)
    {
        cin>>a>>b>>c>>d>>e;
        add(a,b,d,e);
        if(c==0)
        add(b,a,d,e);
    }
    cin>>s>>e;
    dij(s);
    //printf("Time = %d: ",span[e]);
    print(pret[e]);
    //printf("%d\n",e);
    //printf("Distance = %d: ",dis[e]);
    prind(pred[e]);
    //printf("%d\n",e);
    int flag=0;
    if(cnt1==cnt2)
    {
        int i;
        for(i=1;i<=cnt1;i++)
        {
            if(ans1[i]!=ans2[i])
            {
                break;
            }
        }
        if(i==cnt1+1) flag=1;
    }
    if(flag==1)
    {
        printf("Time = %d; Distance = %d: ",span[e],dis[e]);
        for(int i=1;i<=cnt1;i++)
        printf("%d => ",ans1[i]);
        printf("%d\n",e);
    }
    else
    {
        printf("Time = %d: ",span[e]);
        for(int i=1;i<=cnt1;i++)
        printf("%d => ",ans1[i]);
        printf("%d\n",e);
        printf("Distance = %d: ",dis[e]);
        for(int i=1;i<=cnt2;i++)
        printf("%d => ",ans2[i]);
        printf("%d\n",e);
    }
    return 0;
}

           

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