【HDOJ】2267 How Many People Can Survive

BFS。

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <queue>
 5 using namespace std;
 6 
 7 #define MAXN 305
 8 
 9 typedef struct node_st {
10     int x, y;
11     node_st() {}
12     node_st(int xx, int yy) {
13         x = xx; y = yy;
14     }
15 } node_st;
16 
17 char map[MAXN][MAXN];
18 bool visit[MAXN][MAXN];
19 int direct[4][2] = {-1,0,1,0,0,-1,0,1};
20 int n, m, f, s;
21 
22 bool getNext(int *x, int *y) {
23     for (int i=0; i<n; ++i) {
24         for (int j=0; j<m; ++j) {
25             if (map[i][j]!='#' && visit[i][j]==false) {
26                 *x = i;
27                 *y = j;
28                 return true;
29             }
30         }
31     }
32     return false;
33 }
34 
35 void bfs() {
36     queue<node_st> que;
37     node_st node;
38     int ff, ss, x, y;
39     bool flg;
40     int i;
41 
42     f = s = 0;
43     memset(visit, false, sizeof(visit));
44     while (1) {
45         if (!getNext(&x, &y))
46             break;
47         ff = ss = 0;
48         if (map[x][y] == 'o')   ++ff;
49         if (map[x][y] == 'v')   ++ss;
50         que.push(node_st(x, y));
51         visit[x][y] = true;
52         flg = false;
53 
54         while (!que.empty()) {
55             node = que.front();
56             que.pop();
57             for (i=0; i<4; ++i) {
58                 x = node.x + direct[i][0];
59                 y = node.y + direct[i][1];
60                 if (x<0 || x>=n || y<0 || y>=m) {
61                     flg = true;
62                     continue;
63                 }
64                 if (map[x][y]!='#' && !visit[x][y]) {
65                     que.push(node_st(x, y));
66                     visit[x][y] = true;
67                     if (map[x][y] == 'o')   ++ff;
68                     if (map[x][y] == 'v')   ++ss;
69                 }
70             }
71         }
72         if (!flg) {
73             if (ff > ss)    f += ff;
74             if (ff < ss)    s += ss;
75         }
76     }
77     printf("%d %d
", f, s);
78 }
79 
80 int main() {
81     int i;
82 
83     while (scanf("%d %d", &n, &m) != EOF) {
84         for (i=0; i<n; ++i)
85             scanf("%s", map[i]);
86         bfs();
87     }
88 
89     return 0;
90 }
原文地址:https://www.cnblogs.com/bombe1013/p/3843847.html