hdu 1690 Bus System

floyd算法。这题目比较操蛋，首先INF需要比较大，我选择了INF = 0xffffffffffffff。还有一点就是%lld会挂掉的，用%I64d才能AC。

#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn = 105;
__int64 INF = 0xffffffffffffff;
__int64 x[maxn], jz[maxn][maxn], A[maxn][maxn];
int n, m;
void floyd()
{
    int i, j, k;
    for (i = 0; i <= n; i++)
    for (j = 0; j <= n; j++)
        A[i][j] = jz[i][j];

    for (k = 1; k <= n; k++)
    {
        for (i = 1; i <= n; i++)
        {
            for (j = 1; j <= n; j++)
            {
                if (k == i || k == j) continue;
                if (A[i][k] == INF || A[k][j] == INF) continue;
                else
                {
                    if (A[i][k] + A[k][j] < A[i][j])
                    {
                        A[i][j] = A[i][k] + A[k][j];
                    }
                }
            }
        }
    }
}

int main()
{
    __int64 l1, l2, l3, l4, c1, c2, c3, c4;
    int i, j, sb, _;
    scanf("%d", &sb);
    for (_ = 1; _ <= sb; _++)
    {
        scanf("%I64d%I64d%I64d%I64d%I64d%I64d%I64d%I64d", &l1, &l2, &l3, &l4, &c1, &c2, &c3, &c4);
        scanf("%d%d", &n, &m);
        for (i = 0; i <= n; i++)
        {
            for (j = 0; j <= n; j++)
            {
                if (i == j) jz[i][j] = 0;
                else jz[i][j] = INF;
            }
        }
        for (i = 1; i <= n; i++) scanf("%I64d", &x[i]);
        for (i = 1; i <= n; i++)
        {
            for (j = 1; j <= n; j++)
            {
                if (i == j) continue;
                __int64 jl = abs(x[i] - x[j]);
                if (jl > 0 && jl <= l1){ jz[i][j] = c1; jz[j][i] = c1; }
                else if (jl > l1 && jl <= l2){ jz[i][j] = c2; jz[j][i] = c2; }
                else if (jl > l2 && jl <= l3) { jz[i][j] = c3; jz[j][i] = c3; }
                else if (jl > l3 && jl <= l4) { jz[i][j] = c4; jz[j][i] = c4; }
            }
        }
        floyd();
        int u, v;
        printf("Case %d:\n", _);
        for (i = 0; i < m; i++)
        {
            scanf("%d%d", &u, &v);
            if (A[u][v] != INF)printf("The minimum cost between station %d and station %d is %I64d.\n", u, v, A[u][v]);
            else printf("Station %d and station %d are not attainable.\n", u, v);
        }
    }
    return 0;
}