import algorithm, sequtils, strutils
var
  n: int = stdin.readline.parseInt
  a: seq[seq[int]] = mapIt(0..<n, stdin.readline.split.map(parseInt))
  ans: seq[int]
for i in 0..<n:
  a[i].delete(0)
for i in 0..<n:
  if a[i].len == 0:
    a.delete(i)
    n.dec
while a.len > 0:
  var tmp: seq[int]
  for i in 0..<n:
    tmp.add(a[i][0])
    a[i].delete(0)
  for i in 0..<n:
    if a[i].len == 0:
      a.delete(i)
      n.dec
  tmp.sort()
  ans.add(tmp)
for i in ans:
  stdout.write(i)
  stdout.write(" ")