my-solutions/leetcode/0036-valid-sudoku/main.rb

63 lines
1.1 KiB
Ruby

# @param {Character[][]} board
# @return {Boolean}
def is_valid_sudoku(board)
# Check rows
return false unless sudoku_rows_valid?(board)
# Check columns
return false unless sudoku_columns_valid?(board)
# Check sub-boxes
return false unless sudoku_sub_boxes_valid?(board)
true
end
def sudoku_rows_valid?(board)
board.each do |row|
digits = []
row.each do |cell|
return false if digits.include?(cell)
digits.push(cell) if cell != '.'
end
end
true
end
def sudoku_columns_valid?(board)
9.times do |i|
digits = []
board.each do |row|
cell = row[i]
return false if digits.include?(cell)
digits.push(cell) if cell != '.'
end
end
true
end
def sudoku_sub_boxes_valid?(board)
3.times do |i|
# Select 3 rows
rows = board[i * 3..i * 3 + 2]
3.times do |j|
digits = []
rows.each do |row|
# Select 3 columns
cols = row[j * 3..j * 3 + 2]
cols.each do |cell|
return false if digits.include?(cell)
digits.push(cell) if cell != '.'
end
end
end
end
true
end