32pts求助

shipeiqian @ 2022-08-09 10:41:04

#include <bits/stdc++.h>
using namespace std;
int n,a[35][35],b[35][35];
int dx[4]={0,0,-1,1};
int dy[4]={-1,1,0,0};
bool check(int x,int y){
    if(x<1||y<1||x>n||y>n)return false;
    if(a[x][y])return false;
    return true;
}
void dfs(int x,int y){
    if(check(x,y)){
        a[x][y]=1;
        for(int i=0;i<4;i++)    {
            int nx=x+dx[i];
            int ny=y+dy[i];
            dfs(nx,ny);
        }
    }
}
int main(){
    cin >>n;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            cin >>b[i][j];
            if(!b[i][j])a[i][j]=0;
            else a[i][j]=2;
        }
    }
    dfs(1,1);
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++){
            if(!a[i][j])cout <<2 <<" ";
            else cout <<b[i][j] <<" ";
        }
        cout <<"\n";
    }
    return 0;
}

by MONED @ 2022-08-09 11:07:02

要判断外面一圈

0 0 0 1 1

0 0 1 1 0

0 1 0 0 0

1 0 0 0 0

用你的代码就错了

从0 0开始dfs

by MONED @ 2022-08-09 11:10:36

我给的样例不用在意

by MONED @ 2022-08-09 11:14:38

你要是在不会 代码奉上

#include <bits/stdc++.h>
using namespace std;

const int K=35;
int n,dx[4]={0,1,0,-1},dy[4]={1,0,-1,0};
bool b1[K][K],b2[K][K];

void dfs(int x,int y)
{
    if(x<0 || y<0 || x>n+1 || y>n+1 || !b2[x][y]) return;
    b2[x][y]=0;
    for(int i=0;i<4;++i) dfs(x+dx[i],y+dy[i]);
}

int main(){
    cin>>n;
    for(int i=1;i<=n;++i) for(int j=1;j<=n;++j) cin>>b1[i][j];
    for(int i=0;i<=n+1;++i) for(int j=0;j<=n+1;++j) b2[i][j]=!b1[i][j];
    dfs(0,0);
    for(int i=1;i<=n;++i)
    {
        for(int j=1;j<=n;++j)
        {
            if(b2[i][j]) cout<<2<<" ";
            else cout<<b1[i][j]<<" ";
        }
        cout<<endl;
    }
    return 0;
}

by shipeiqian @ 2022-08-09 11:23:45

@MONED 懂了，谢谢