H, W = map(int, input().split())
A = [list(map(int, input().split())) for _ in range(H)]

data = []
for i in range(H):
    for j in range(W):
        data.append(A[i][j])
data.sort()
ans = [[-1] * (W) for _ in range(H)]
for k in range(H*W):
    i, j = divmod(k, W)
    ans[i][j] = data[k]

for a in ans:
    print(*a)