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. Draw the maximum element below the main diagonal. The elements of the main diagonal are also taken into account.

n = int(input())
matrix = [[int(i) for i in input().split()] for _ in range(n)]

def main_diagonal(matrix, n):
	return [matrix[i][j] for i in range(n) for j in range(n) if i + j == n - 1]

def main_diagonal_max(matrix, n):
	return max(main_diagonal(matrix, n))

print(main_diagonal_max(matrix, n))