HDU 1690 Bus System(多源最短路径)

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http://acm.hdu.edu.cn/showproblem.php?pid=1690

无穷大设置的不好，WA了3次，最后干脆改成-1过了。

#include <cstdio>#include <iostream>#include  <cstring>using namespace std;const int maxn = 100+5;const __int64 inf=-1;__int64 map[maxn][maxn],dist[maxn][maxn];__int64 L[5],C[5];__int64 x[maxn];__int64 abss(__int64 x){    if(x<0) x=x*(-1);    if(x<=L[1]) return C[1];    else if(x<=L[2]) return C[2];    else if(x<=L[3]) return C[3];    else if(x<=L[4]) return C[4];    return inf;}int n;void floyd(){    for(int i=1;i<=n;i++)        for(int j=1;j<=n;j++){           if(i==j) dist[i][j]=0;           else dist[i][j]=map[i][j];        }    for(int k=1;k<=n;k++)        for(int i=1;i<=n;i++)            for(int j=1;j<=n;j++)                if(dist[i][k]!=-1&&dist[k][j]!=-1&&(dist[i][j]>dist[i][k]+dist[k][j]||dist[i][j]==-1))                    dist[i][j]=dist[i][k]+dist[k][j];}int main(){    int T,m;    scanf("%d",&T);    for(int kas=1;kas<=T;kas++)    {        for(int i=1;i<5;i++) scanf("%I64d",&L[i]);        for(int i=1;i<5;i++) scanf("%I64d",&C[i]);        scanf("%d%d",&n,&m);        for(int i=1;i<=n;i++){            scanf("%I64d",&x[i]);            for(int j=1;j<i;j++)               map[i][j]=map[j][i]=abss(x[i]-x[j]);        }        floyd();        printf("Case %d:\n",kas);        while(m--)        {            int u,v;            scanf("%d%d",&u,&v);            if(dist[u][v]!=-1)                printf("The minimum cost between station %d and station %d is %I64d.\n",u,v,dist[u][v]);            else                printf("Station %d and station %d are not attainable.\n",u,v);        }    }    return 0;}