Hdu 1690 Bus System (Shortest Path)

Problem:

Link: Click to open the link

Question:

Ideas:

Code:

#include 
 
  #include 
  
   #include 
   
    using namespace std;#define INF 1000000000000typedef __int64 LL;const int N = 110;__int64 dis[N][N],place[N];__int64 L1,L2,L3,L4,C1,C2,C3,C4;int n,m;LL judge(LL x){    if(x < 0)        x *= -1;    if(x > 0 && x <= L1)        return C1;    else if(x > L1 && x <= L2)        return C2;    else if(x > L2 && x <= L3)        return C3;    else if(x > L3 && x <= L4)        return C4;    else        return INF;}void floyd(){    for(int k=1; k<=n; k++)    {        for(int i=1; i<=n; i++)        {            for(int j=1; j<=n; j++)            {                if(dis[i][j] > dis[i][k] + dis[k][j] && dis[i][k] != INF && dis[k][j] != INF)                    dis[i][j] = dis[i][k] + dis[k][j];            }        }    }}int main(){    //freopen("input.txt","r",stdin);    int t;    int kase = 1;    cin>>t;    while(t--)    {        scanf("%I64d%I64d%I64d%I64d%I64d%I64d%I64d%I64d",&L1,&L2,&L3,&L4,&C1,&C2,&C3,&C4);        scanf("%d%d",&n,&m);        for(int i=1; i<=n; i++)        {            scanf("%I64d",&place[i]);        }        for(int i=1; i<=n; i++)        {            for(int j=i+1; j<=n; j++)            {                __int64 x = place[i] - place[j];                dis[i][j] = dis[j][i] = judge(x);            }        }        floyd();        printf("Case %d:\n",kase++);        for(int i=1; i<=m; i++)        {            int st,ed;            scanf("%d%d",&st,&ed);            if(dis[st][ed] != INF)                printf("The minimum cost between station %d and station %d is %I64d.\n",st,ed,dis[st][ed]);            else                printf("Station %d and station %d are not attainable.\n",st,ed);        }    }    return 0;}
   
  
 

----------------------------------------------------------

Gains:

---------------------------------------------------------

Fighting, never shrinking; fighting, never stopping ~~~~~~~~~~~~~~