The input is a natural number n — the number of rows and columns in the square matrix. Next, the elements of the matrix are entered line by line with a space. Output the maximum element excluding the area above the main diagonal.

def max(n):
  max = 0
  for i in range(n):
    a = [int(i) for i in input().split()]
    for j in range(n):
      if a[j] > max and i < j:
        max = a[j]
  return max