A1091.cpp

#include <cstdio>
#include<queue>
using namespace std;
struct node{
	int x, y, z;
}Node;
int n, m, slice, T;
int pixel[1290][130][61];
bool inq[1290][130][61] = {false};
int X[6] = {0, 0, 0, 0, 1, -1};
int Y[6] = {0, 0, 1, -1, 0, 0};
int Z[6] = {1, -1, 0, 0, 0, 0};

bool judge(int x, int y, int z){
	if(x >= n || x < 0 || y >= m || y < 0 || z > slice || z < 0)
		return false;
	if(pixel[x][y][z] == 0 || inq[x][y][z] == true)
		return false;
	
	return true;
}

int BFS(int x, int y, int z){
	int tot = 0;
	queue<node> Q;
	Node.x = x, Node.y = y, Node.z = z;
	Q.push(Node);
	inq[x][y][z] = true;
	while(!Q.empty()){
		node top = Q.front();
		Q.pop();
		tot++;
		for(int i = 0; i < 6; i++){
			int newX = top.x + X[i];
			int newY = top.y + Y[i];
			int newZ = top.z + Z[i];
			if(judge(newX, newY, newZ)){
				Node.x = newX, Node.y = newY, Node.z = newZ;
				Q.push(Node);
				inq[newX][newY][newZ] = true;
			}
		}
	}
	if(tot >= T)
		return tot;
	else
		return 0;
}

int main(){
	scanf("%d%d%d", &n, &m, &slice, &T);
	for(int z = 0; z < slice; z++){
		for(int x = 0; x < n; x++){
			for(int y = 0; y < m; y++){
				scanf("%d", &pixel[x][y][z]);
			}
		}
	}
	int ans = 0;
	for(int z = 0; z < slice; z++){
		for(int x = 0; x < n; x++){
			for(int y = 0; y < m; y++){
				if(pixel[x][y][z] == 1 && inq[x][y][z] == false){
					ans += BFS(x, y, z);
				}
			}
		}
	}
	printf("%d\n", ans);
	return 0;
}


//方法二
#include <cstdio>
#include <queue>
using namespace std;
struct node {
    int x, y, z;
};
int m, n, l, t;
int X[6] = {1, 0, 0, -1, 0, 0};
int Y[6] = {0, 1, 0, 0, -1, 0};
int Z[6] = {0, 0, 1, 0, 0, -1};
int arr[1300][130][80];
bool visit[1300][130][80];
bool judge(int x, int y, int z) {
    if(x < 0 || x >= m || y < 0 || y >= n || z < 0 || z >= l) return false;
    if(arr[x][y][z] == 0 || visit[x][y][z] == true) return false;
	
    return true;
}
int bfs(int x, int y, int z) {
    int cnt = 0;
    node temp;
    temp.x = x, temp.y = y, temp.z = z;
    queue<node> q;
    q.push(temp);
    visit[x][y][z] = true;
    while(!q.empty()) {
        node top = q.front();//取出并访问队首元素
        q.pop();					//队首元素出列
        cnt++;
        for(int i = 0; i < 6; i++) {//循环六次，得到6个增量方向
            int tx = top.x + X[i];
            int ty = top.y + Y[i];
            int tz = top.z + Z[i];
            if(judge(tx, ty, tz)) {//
                visit[tx][ty][tz] = true;
                temp.x = tx, temp.y = ty, temp.z = tz;
                q.push(temp);
            }
        }
    }
    if(cnt >= t)
        return cnt;
    else
        return 0;
    
}
int main() {
    scanf("%d %d %d %d", &m, &n, &l, &t);
	
    for(int i = 0; i < l; i++)
        for(int j = 0; j < m; j++)
            for(int k = 0; k < n; k++)
                scanf("%d", &arr[j][k][i]);
			
    int ans = 0;
    for(int i = 0; i < l; i++) {
        for(int j = 0; j < m; j++) {
            for(int k = 0; k < n; k++) {
                if(arr[j][k][i] == 1 && visit[j][k][i] == false)
                    ans += bfs(j, k, i);
            }
        }
    }
    printf("%d", ans);
    return 0;
}