import java.util.Arrays;
import java.util.Scanner;

// 给出一个不大于9的正整数n，输出n×n的蛇形方阵。
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[][] a = new int[n][n];
        int total = 1;
        int x = 0;
        int y = 0;
        a[x][y] = 1;
        while (total <n * n) {
            while (y<n-1 && a[x][y+1] == 0) {
                a[x][++y] = ++total;
            }
            while (x<n-1 && a[x+1][y] == 0) {
                a[++x][y] = ++total;
            }
            while (y>0 && a[x][y-1] == 0) {
                a[x][--y] = ++total;
            }
            while (x>0 && a[x-1][y] == 0) {
                a[--x][y] = ++total;
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                System.out.printf("%3d",a[i][j]);
            }
            System.out.println();
        }
    }
}

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