【HDOJ】3316 Mine sweeping

简单BFS。

 #include <iostream>
 #include <cstdio>
 #include <cstring>
 #include <cstdlib>
 #include <queue>
 using namespace std;

 #define MAXN 105

 typedef struct node_t {
     int x, y;
     node_t() {}
     node_t(int xx, int yy) {
         x = xx; y = yy;
     }
 } node_t;

 char map[MAXN][MAXN];
 char ans[MAXN][MAXN];
 bool visit[MAXN][MAXN];
 int dir[][] = {
     {-,},{,},{,},{,-},
     {,},{,-},{-,},{-,-}
 };
 node_t s;
 int n;

 bool check(int x, int y) {
     return x< || x>=n || y< || y>=n;
 }

 void bfs() {
     int i, j, k, tmp;
     int x, y, v;
     int xx[], yy[], m;
     queue<node_t> Q;
     node_t nd;

     memset(visit, false, sizeof(visit));
     memset(ans, '.', sizeof(ans));
     visit[s.x][s.y] = true;
     for (i=; i<n; ++i)
         ans[i][n] = '\0';
     Q.push(s);

     while (!Q.empty()) {
         nd = Q.front();
         Q.pop();
         v = m = ;
         for (i=; i<; ++i) {
             x = nd.x + dir[i][];
             y = nd.y + dir[i][];
             if (check(x, y))
                 continue;
             xx[m] = x;
             yy[m] = y;
             ++m;
             if (map[x][y] == 'X')
                 ++v;
         }
         ans[nd.x][nd.y] = v+'';
         if (v == ) {
             for (i=; i<m; ++i) {
                 if (!visit[xx[i]][yy[i]]) {
                     visit[xx[i]][yy[i]] = true;
                     Q.push(node_t(xx[i], yy[i]));
                 }
             }
         }
     }
 }

 int main() {
     int i, j;

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

     while (scanf("%d", &n) != EOF) {
         for (i=; i<n; ++i)
             scanf("%s", map[i]);
         scanf("%d %d", &s.x, &s.y);

         if (map[s.x][s.y] == 'X') {
             printf("it is a beiju!\n\n");
         } else {
             bfs();
             for (i=; i<n; ++i)
                 printf("%s\n", ans[i]);
             printf("\n");
         }
     }

     return ;
 }