Pat-1018 public bike Management (30)

If you use Dijkstra directly, you can only get 22 and four cases.

#include<stdio.h>#include<stack>using namespace std;int bike_count[510];int bike_sum[510]; int bike_sum_num[510];int map[510][510];bool visited[510];int d[510];int pre[510];int Max=0xffffffff>>1;//max=max>>1;int findMin(int n){    int min=Max,index=-1;    for(int i=0;i<=n;i++)    {      if(!visited[i]&&d[i]<min)      {          min=d[i];          index=i;      }    }    return index;} int main(){     int maxc,n,sp,m;     int a,b,val;     freopen("1018-in.txt","r",stdin);     freopen("1018-out.txt","w",stdout);     while(scanf("%d%d%d%d",&maxc,&n,&sp,&m)!=EOF)     {       for(int i=0;i<=n;i++)//init map         {          for(int j=0;j<=n;j++)          {             map[i][j]=Max;          }          visited[i]=false;          d[i]=Max;          bike_sum[i]=0;          bike_sum_num[i]=0;          pre[i]=0;        }        bike_count[0]=0;        for(int i=1;i<=n;i++)        {          scanf("%d",&bike_count[i]);        }                for(int i=0;i<m;i++)        {          scanf("%d%d%d",&a,&b,&val);          map[a][b]=map[b][a]=val;        }                //begin dijkstra        int index;        d[0]=0;        pre[0]=-1;         while(true)         {            index=findMin(n);            //for(int s=0;s<n;s++)             // printf("%d ",d[s]);             //("\n");            visited[index]=true;            //printf("index=%d\n",index);            if(index==-1)              break;            for(int i=0;i<=n;i++)            {              if(map[i][index]!=Max&&d[i]>d[index]+map[index][i])              {                 d[i]=d[index]+map[index][i];                 bike_sum[i]=bike_sum[index]+bike_count[i];                 bike_sum_num[i]=bike_sum_num[index]+1;                 pre[i]=index;                 //printf( "0 i=%d,index=%d %d\n",i,index,bike_sum[i]);              }              else if(map[i][index]!=Max&&d[i]==d[index]+map[index][i])              {                 double a=(bike_sum[i]/(bike_sum_num[i]*1.0));                 double b=(bike_sum[index]+bike_count[i])/((bike_sum_num[index]+1)*1.0);                 //printf("%lf %lf\n",a,b);                 if(a>maxc/2.0&&b>=maxc/2.0&&a>b)                 {                      d[i]=d[index]+map[index][i];                      bike_sum[i]=bike_sum[index]+bike_count[i];                      bike_sum_num[i]=bike_sum_num[index]+1;                      pre[i]=index;                      //printf("1 i=%d,index=%d,%d\n",i,index,bike_sum[i]);                 }                 if(a<maxc/2.0&&b<=maxc/2.0&&a<b)                 {                      d[i]=d[index]+map[index][i];                      bike_sum[i]=bike_sum[index]+bike_count[i];                      bike_sum_num[i]=bike_sum_num[index]+1;                      pre[i]=index;                      //printf("2 i=%d,index=%d,%d\n",i,index,bike_sum[i]);                 }                  if(a<maxc/2.0&&b>=maxc/2.0)                 {                      d[i]=d[index]+map[index][i];                      bike_sum[i]=bike_sum[index]+bike_count[i];                      bike_sum_num[i]=bike_sum_num[index]+1;                      pre[i]=index;                      //printf("3 i=%d,index=%d,%d\n",i,index,bike_sum[i]);                 }                 /*if(b==maxc/2.0)                 {                      d[i]=d[index]+map[index][i];                      bike_sum[i]=bike_sum[index]+bike_count[i];                      bike_sum_num[i]=bike_sum_num[index]+1;                      pre[i]=index;                 }*/                 //printf("4 i=%d,index=%d,%d\n",i,index,bike_sum[i]);              }            }         }//while(true)         //printf("%d\n",bike_sum[sp]);          //printf("%d\n",bike_sum_num[sp]);           int mod=bike_sum_num[sp]*maxc/2-bike_sum[sp];          printf("%d ",mod>=0?mod:0);          int p=sp;          stack<int> path;          path.push(sp);          while(true)          {             p=pre[p];             if(p==-1)               break;             path.push(p);          }          while(!path.empty())          {              printf("%d",path.top());              if(path.size()!=1)               printf("->");              path.pop();          }              printf(" %d\n",mod<=0?0-mod:0);     }    return 0;} 

I found a pitfall on the Internet, that is, the vehicles at the back of the site cannot transport the site before the meeting. Therefore, there will be four tests that fail and need to be implemented by dijskstra + DFS. Save all the paths.

Make up later.

Pat-1018 public bike Management (30)