PAT甲级1091 Acute Stroke【三维bfs】

题目：https://pintia.cn/problem-sets/994805342720868352/problems/994805375457411072

题意：

求三维的连通块

思路：

简单bfs

 #include<cstdio>
 #include<cstdlib>
 #include<map>
 #include<set>
 #include<iostream>
 #include<cstring>
 #include<algorithm>
 #include<vector>
 #include<cmath>
 #include<stack>
 #include<queue>

 #define inf 0x7fffffff
 using namespace std;
 typedef long long LL;
 typedef pair<string, string> pr;

 int m, n, l, t;
 struct node{
     int x, y, z;
     node(){
     }
     node(int _x, int _y, int _z){
         x = _x;
         y = _y;
         z = _z;
     }
 };

 int dx[] = {, , , , , -};
 int dy[] = {, -, , , , };
 int dz[] = {, , , -, , };
 bool space[][][];
 bool vis[][][];
 int tot = ;

 bool check(int i, int j, int k)
 {
     if(i <  || i >= m || j <  || j >= n || k <  || k >= l)return false;
     else return true;
 }

 void bfs(int x, int y, int z)
 {
     queue<node>que;
     que.push(node(x, y, z));
     vis[x][y][z] = true;
     int cnt = ;
     while(!que.empty()){
         node now = que.front();que.pop();
         for(int i = ; i < ; i++){
             int a = now.x + dx[i], b = now.y + dy[i], c = now.z + dz[i];
             if(check(a, b, c) && !vis[a][b][c] && space[a][b][c]){
                 que.push(node(a, b, c));
                 vis[a][b][c] = true;
                 cnt++;
             }
         }
     }
     if(cnt >= t){
         tot += cnt;
     }
 }

 int main()
 {
     scanf("%d%d%d%d", &m, &n, &l, &t);
     for(int k = ; k < l; k++){
         for(int i = ; i < m; i++){
             for(int j = ; j < n; j++){
                 scanf("%d", &space[i][j][k]);
             }
         }
     }

     for(int k = ; k < l; k++){
         for(int i = ; i < m; i++){
             for(int j = ; j < n; j++){
                 if(!vis[i][j][k] && space[i][j][k])
                     bfs(i, j, k);
             }
         }
     }
     printf("%d\n", tot);
     return ;
 }