Write a program that prints the maximum element of a square matrix whose elements are entered from the keyboard, below the main diagonal. The elements of the main diagonal are also taken into account.

n = int(input("Enter the value of n: "))

def max_of_matrix(n):
  matrix = []
  sum = 0
  for i in range(n):
      a = []
      for j in range(n):
          a.append(int(input()))
      matrix.append(a)

  for i in range(n):
      for j in range(n):
          if i < j:
              sum += matrix[i][j]
          
  return sum

print(max_of_matrix(n)