The Largest Generation (25)（BFS)(PAT甲级)

#include<bits/stdc++.h>
using namespace std;
int n,m,l,t;
int a[1307][137][67];
int vis[1307][137][67];
typedef struct{
    int x,y,z;
}node;
int xx[6]={0,0,0,0,1,-1};
int yy[6]={0,0,1,-1,0,0};
int zz[6]={1,-1,0,0,0,0};
node p;
int bfs(int x,int y,int z){
    queue<node>q;
    vis[x][y][z]=1;
    p.x=x;
    p.y=y;
    p.z=z;
    q.push(p);
    int sum=0;
    while(!q.empty()){
        node tmp=q.front();
        q.pop();
        sum++;
        for(int i=0;i<6;++i){
            int tx=tmp.x+xx[i];
            int ty=tmp.y+yy[i];
            int tz=tmp.z+zz[i];
            if(tx>0&&tx<=n&&ty>0&&ty<=m&&tz>0&&tz<=l&&a[tx][ty][tz]&&!vis[tx][ty][tz]){
                p.x=tx;
                p.y=ty;
                p.z=tz;
                q.push(p);
                vis[tx][ty][tz]=1;
            }
        }
    }
    if(sum>=t)
        return sum;
    return 0;
}
int main(){
    std::ios::sync_with_stdio(false);
    cin>>n>>m>>l>>t;
    for(int i=1;i<=l;++i)
        for(int j=1;j<=n;++j)
            for(int k=1;k<=m;++k)
                cin>>a[j][k][i];
    int ans=0;
    for(int i=1;i<=l;++i)
        for(int j=1;j<=n;++j)
            for(int k=1;k<=m;++k)
                if(a[j][k][i]&&!vis[j][k][i])
                    ans+=bfs(j,k,i);
    cout<<ans;
    return 0;
}