#!/usr/bin/env python3

import sys

def parsematrix(m, n):
    Mat = []
    for i in range(m):
        A = sys.stdin.readline().split()
        row = []
        for j in range(n):
            row.append(int(A[j]))
        Mat.append(row)
    return Mat

def printmatrix(Mat, m, n):
    if m == 0 or n == 0:
        return

    i = 0
    min_j = -1
    max_j = n
    min_i = -1
    max_i = m
    j = 0
    direction = 0 # 0 right, 1 down, 2 left, 3 up

    while i > min_i and i < max_i and j < max_j and j > min_j:
        if i == 0 and j == 0:
            print(Mat[i][j], end="")
        else:
            print(" " + str(Mat[i][j]), end="")

        if direction == 0 and j == n - i - 1:
            min_i = i
            direction = 1
        if direction == 1 and i == m - (n - j):
            max_j = j
            direction = 2
        if direction == 2 and j == m - i - 1:
            max_i = i
            direction = 3
        if direction == 3 and j == i - 1:
            min_j = j
            direction = 0

        if direction == 0:
            j = j + 1
        elif direction == 1:
            i = i + 1
        elif direction == 2:
            j = j - 1
        else:
            i = i - 1

if __name__ == "__main__":
    A = sys.stdin.readline().split()
    m = int(A[0])
    n = int(A[1])
    Mat = parsematrix(m, n)
    printmatrix(Mat, m, n)