【HDOJ】3295 An interesting mobile game

  1 /* 3295 */
  2 #include <iostream>
  3 #include <cstdio>
  4 #include <cstring>
  5 #include <cstdlib>
  6 #include <queue>
  7 using namespace std;
  8 
  9 typedef struct {
 10     char m[6][6];
 11     char x, y;
 12     char s, c;
 13 } node_t;
 14 
 15 typedef struct subNode_t {
 16     char x, y;
 17     subNode_t() {}
 18     subNode_t(char xx, char yy) {
 19         x = xx; y = yy;
 20     }
 21 } subNode_t;
 22 
 23 bool visit[6][6];
 24 node_t beg, cur;
 25 int n, m, cnt;
 26 char dir[4][2] = {
 27     -1,0,0,-1,1,0,0,1
 28 };
 29 queue<node_t> Q;
 30 queue<subNode_t> q;
 31 
 32 inline bool check(char x, char y) {
 33     return x<0 || x>=n || y<0 || y>=m;
 34 }
 35 
 36 void remove(char x, char y, char cl) {
 37     char i, j, k;
 38     subNode_t nd;
 39     
 40     ++cur.s;
 41     cur.m[x][y] = 0;
 42     visit[x][y] = true;
 43     --cur.c;
 44     q.push(subNode_t(x, y));
 45     
 46     while (!q.empty()) {
 47         nd = q.front();
 48         q.pop();
 49         for (i=0; i<4; ++i) {
 50             x = nd.x + dir[i][0];
 51             y = nd.y + dir[i][1];
 52             if (check(x, y) || visit[x][y])
 53                 continue;
 54             if (cur.m[x][y] == cl) {
 55                 cur.m[x][y] = 0;
 56                 visit[x][y] = true;
 57                 --cur.c;
 58                 q.push(subNode_t(x, y));
 59             }
 60         }
 61     }
 62 }
 63 
 64 node_t shift() {
 65     char i, j, k, r;
 66     bool flag;
 67     node_t nd;
 68     
 69     // copy from cur
 70     nd.s = cur.s;
 71     nd.c = cur.c;
 72     nd.x = cur.x;
 73     nd.y = cur.y;
 74     memset(nd.m, 0, sizeof(nd.m));
 75     
 76     // fall down
 77     r = 0;
 78     for (j=0; j<m; ++j) {
 79         k = n-1;
 80         for (i=n-1; i>=0; --i)
 81             if (cur.m[i][j])
 82                 nd.m[k--][r] = cur.m[i][j];
 83         if (k < n-1)
 84             ++r;
 85     }
 86     
 87     return nd;
 88 }
 89 
 90 char bfs() {
 91     char i, j, k;
 92     node_t nd;
 93     
 94     while (!Q.empty())
 95         Q.pop();
 96     
 97     memset(visit, false, sizeof(visit));
 98     for (i=0; i<n; ++i) {
 99         for (j=0; j<n; ++j) {
100             if (beg.m[i][j] && !visit[i][j]) {
101                 cur = beg;
102                 remove(i, j, beg.m[i][j]);
103                 nd = shift();
104                 Q.push(nd);
105             }
106         }
107     }
108     
109     while (!Q.empty()) {
110         beg = Q.front();
111         Q.pop();
112         if (beg.c == 0)
113             return beg.s;
114         memset(visit, false, sizeof(visit));
115         for (i=0; i<n; ++i) {
116             for (j=0; j<m; ++j) {
117                 if (beg.m[i][j] && !visit[i][j]) {
118                     cur = beg;
119                     remove(i, j, beg.m[i][j]);
120                     nd = shift();
121                     Q.push(nd);
122                 }
123             }
124         }
125     }
126     
127     return 0;
128 }
129 
130 int main() {
131     int i, j, k;
132     
133     #ifndef ONLINE_JUDGE
134         freopen("data.in", "r", stdin);
135     #endif
136     
137     while (scanf("%d%d",&n,&m) != EOF) {
138         cnt = 0;
139         beg.s = 0;
140         for (i=0; i<n; ++i) {
141             for (j=0; j<m; ++j) {
142                 scanf("%d", &k);
143                 beg.m[i][j] = k;
144                 if (k)
145                     ++cnt;
146             }
147         }
148         beg.c = cnt;
149         k = bfs();
150         printf("%d\n", k);
151     }
152     
153     return 0;
154 }