// Program 20: Merge Both Diagonals in Ascending Order

import java.util.*;
class DiagonalMerge {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        if (n < 1 || n > 20) {
            System.out.println("Invalid order");
            return;
        }
        int[][] a = new int[n][n];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                a[i][j] = sc.nextInt();
            }
        }
        int size = n * 2;
        if (n % 2 == 1) {
            size--;
        }
        int[] merged = new int[size];
        int pos = 0;
        for (int i = 0; i < n; i++) {
            merged[pos++] = a[i][i];
            if (i != n - 1 - i) {
                merged[pos++] = a[i][n - 1 - i];
            }
        }
        for (int i = 1; i < size; i++) {
            int key = merged[i];
            int j = i - 1;
            while (j >= 0 && merged[j] > key) {
                merged[j + 1] = merged[j];
                j--;
            }
            merged[j + 1] = key;
        }
        for (int x : merged) {
            System.out.print(x + " ");
        }
    }
}