【狗狗40】Square Ice

额，简单的BFS，一开始DFS结果栈炸了，加栈也不行 QAQ

#include<cstdio>
#include<queue>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn = 100;
const int dir[6][3] ={{0,0,1},{0,0,-1},{0,1,0},{0,-1,0},{1,0,0},{-1,0,0}};
#define FOR(i,n) for(int i = 0; i < n; i++)
int mat[maxn][maxn][maxn],vis[maxn][maxn][maxn];
int n,m,k,s,v,a,b,c,area,ans;
bool judge(int x,int y,int z){
    if(x >= 0 && x < n && y >= 0 && y < m && z >= 0 && z < k) return true;
    return false;
}
void dfs(int x,int y,int z){
    queue<int>qx; queue<int>qy; queue<int>qz;
    qx.push(x); qy.push(y); qz.push(z);
    vis[x][y][z] = 1;
    while(!qx.empty()){
        int px = qx.front(),py = qy.front(), pz = qz.front();
        qx.pop(); qy.pop(); qz.pop();
        for(int i = 0; i < 6; i++){
            int xx = px + dir[i][0], yy = py + dir[i][1], zz = pz + dir[i][2];
            if(judge(xx,yy,zz) && !mat[xx][yy][zz] && !vis[xx][yy][zz]){
                vis[xx][yy][zz] = 1;
                qx.push(xx); qy.push(yy); qz.push(zz);
            }
        }
    }
    return;
}
int main(){
    while(scanf("%d%d%d%d",&n,&m,&k,&s)){
        if(!n && !m && !k && !s) break;
        area = n * m;
        ans = 0;
        memset(mat,0,sizeof(mat));
        memset(vis,0,sizeof(vis));
        FOR(i,s){
             scanf("%d",&v);
             c = v / area;
             v %= area;
             a = v % n;
             b = v / n;
             mat[a][b][c] = 1;
        }
        FOR(i,n)FOR(j,m){
                if(!vis[i][j][k - 1] && !mat[i][j][k - 1]) dfs(i,j,k - 1);
                if(!vis[i][j][0] && !mat[i][j][0]) dfs(i,j,0);
            }
        FOR(i,n)FOR(j,k){
                if(!vis[i][m - 1][j] && !mat[i][m - 1][j]) dfs(i,m - 1,j);
                if(!vis[i][0][j] && !mat[i][0][j]) dfs(i,0,j);
            }
        FOR(i,m)FOR(j,k){
                if(!vis[0][i][j] && !mat[0][i][j]) dfs(0,i,j);
                if(!vis[n - 1][i][j] && !mat[n - 1][i][j]) dfs(n - 1,i,j);
            }
        FOR(i,n)FOR(j,m)FOR(h,k)
            if(mat[i][j][h]){
                for(int d = 0; d < 6; d++){
                    int ii = i + dir[d][0];
                    int jj = j + dir[d][1];
                    int hh = h + dir[d][2];
                    if(judge(ii,jj,hh)){
                        if(vis[ii][jj][hh]) ans++;
                    }
                    else ans ++;
                }
            }
        printf("The number of faces needing shielding is %d.\n",ans);
    }
    return 0;
}