1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39

public class Main{
    public static void main(String[] args){
        Scanner scanner=new Scanner(System.in);
        int n=scanner.nextInt();
        int m=scanner.nextInt();
        scanner.close();

        int cols=(n+m-1)/m;
        int[][] matrix=new int[m][cols];

        for(int i=0;i<m;i++){
            for(int j=0;j<cols;j++){
                matrix[i][j]=-1;
            }
        }

        int num=1,top=0,bottom=m-1,left=0,right=cols-1;

        while(num<=n){
            for(int i=left;i<=right&&num<=n;i++) matrix[top][i]=num++;
            top++;
            for(int i=top;i<=bottom&&num<=n;i++) matrix[i][right]=num++;
            right--;
            for(int i=right;i>=left&&num<=n;i--) matrix[bottom][i]=num++;
            bottom--;
            for(int i=bottom;i>=top&&num<=n;i--) matrix[i][left]=num++;
            left++;
        }
        StringBuilder output=new StringBuilder();
        for(int i=0;i<m;i++){
            for(int j=0;j<cols;j++){
                output.append(matrix[i][j]==-1?"*":matrix[i][j]);
                if(j<cols-1) output.append(" ");
            }
            output.append("\n");
        }
        System.out.println(output);
    }
}