废物阿

#include <iostream>
#include <cmath>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int mid=(n+1)/2;
    for (int i=1;i<=n;i++)
    {
        for (int j=1;j<=n;j++)
        {
            if(i<=mid&&j<=mid&&i+j==mid+1)cout<<"#";
            else if(i<=mid&&j>=mid&&j-i==mid-1)cout<<"#";
            else if(i>=mid&&j<=mid&&i-j==mid-1)cout<<"#";
            else if(i>=mid&&j>=mid&&i+j==mid+n)cout<<"#";
            else cout<<".";
        }
        cout<<endl;
    }
    return 0;
}

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