from collections import Counter
H,W=map(int,input().split())

C=Counter()

for i in range(H):
    A=list(map(int,input().split()))
    for a in A:
        C[a]+=1

ANS=[[0]*W for i in range(H)]

for i in range(H):
    for j in range(W):
        for k in range(10):
            if C[k]>0:
                ANS[i][j]=k
                C[k]-=1
                break

for i in range(H):
    print(" ".join(map(str,ANS[i])))