sudoku-isBoardValid.go

func isBoardValid(board *[9][9]int) bool {

	//check duplicates by row
	for row := 0; row < 9; row++ {
		counter := [10]int{}
		for col := 0; col < 9; col++ {
			counter[board[row][col]]++
		}
		if hasDuplicates(counter) {
			return false
		}
	}

	//check duplicates by column
	for row := 0; row < 9; row++ {
		counter := [10]int{}
		for col := 0; col < 9; col++ {
			counter[board[col][row]]++
		}
		if hasDuplicates(counter) {
			return false
		}
	}

	//check 3x3 section
	for i := 0; i < 9; i += 3 {
		for j := 0; j < 9; j += 3 {
			counter := [10]int{}
			for row := i; row < i+3; row++ {
				for col := j; col < j+3; col++ {
					counter[board[row][col]]++
				}
				if hasDuplicates(counter) {
					return false
				}
			}
		}
	}

	return true
}