H, W = map(int, input().split())
A = []
for _ in range(H):
    A.extend(list(map(int, input().split())))
    
A.sort()
for i in range(1, H * W + 1):
    if i % W == 0:
        print(f" {A[i-1]}")
    else:
        print(f"{A[i-1]} ", end="")