【HDOJ】2722 Here We Go(relians) Again

根据矩阵建图，然后求最短路径。

#include <cstdio>
#include <cstring>
#include <cstdlib>

#define L 2520
#define MAXN 600
#define INF 0x2f2f2f2f

int map[MAXN][MAXN];
int dis[MAXN];
int path[MAXN];
int vn;
bool visit[MAXN];

void dijkstra() {
    int i, j, v, min;

    memset(visit, false, sizeof(visit));
    memset(path, 0, sizeof(path));
    visit[0] = true;
    dis[0] = 0;
    for (i=1; i<vn; ++i)
        dis[i] = map[0][i];
    for (j=1; j<vn; ++j) {
        min = INF;
        for (i=0; i<vn; ++i) {
            if (!visit[i] && dis[i]<min) {
                min = dis[i];
                v = i;
            }
        }
        if (min == INF)
            break;
        visit[v] = true;
        for (i=0; i<vn; ++i) {
            if (!visit[i] && dis[i]>min+map[v][i]) {
                dis[i] = min + map[v][i];
                path[i] = v;
            }
        }
    }
}

void output() {
    int i, j;

    for (i=0; i<vn; ++i) {
        for (j=0; j<vn; ++j) {
            printf("%d ", map[i][j]);
        }
        printf("
");
    }
}

int main() {
    int n, m;
    char dir[3];
    int i, j, k, v, r;

#ifndef ONLINE_JUDGE
    freopen("data.in", "r", stdin);
#endif

    while (scanf("%d %d",&n,&m)!=EOF && (n||m)) {
        vn = (m+1) * (n+1);
        memset(map, 0x2f, sizeof(map));
        r = 0;
        for (j=1; j<=m; ++j) {
            scanf("%d %s", &v, dir);
            if (v == 0) {
                map[j-1][j] = map[j][j-1] = INF;
            } else {
                if (dir[0] == '<' || dir[0] == '*')
                    map[j][j-1] = L/v;
                if (dir[0] == '>' || dir[0] == '*')
                    map[j-1][j] = L/v;
            }
        }
        k = m+1;
        for (i=1; i<=n; ++i) {
            // column
            for (j=0; j<=m; ++j) {
                scanf("%d %s", &v, dir);
                if (v == 0) {
                    map[r+j][r+k+j] = map[r+k+j][r+j] = INF;
                } else {
                    if (dir[0] == '^' || dir[0] == '*')
                        map[r+k+j][r+j] = L/v;
                    if (dir[0] == 'v' || dir[0] == '*')
                        map[r+j][r+k+j] = L/v;
                }
            }
            r += k;
            // row
            for (j=1; j<=m; ++j) {
                scanf("%d %s", &v, dir);
                if (v == 0) {
                    map[r+j-1][r+j] = map[r+j][r+j-1] = INF;
                } else {
                    if (dir[0] == '<' || dir[0] == '*')
                        map[r+j][r+j-1] = L/v;
                    if (dir[0] == '>' || dir[0] == '*')
                        map[r+j-1][r+j] = L/v;
                }
            }
        }
        dijkstra();
        if (dis[vn-1] == INF)
            printf("Holiday
");
        else
            printf("%d blips
", dis[vn-1]);
    }

    return 0;
}