// Processing
func (solver *Solver) routine_row1(index1 int) {
	for index2 := range solver.row2s {
		go solver.routine_row2(index1, index2)
	}
}

func (solver *Solver) routine_row2(index1 int, index2 int) {
	for index3 := range solver.row3s {
		go solver.routine_row3(index1, index2, index3)
	}
}

func (solver *Solver) routine_row3(index1 int, index2 int, index3 int) {
	for index4 := range solver.row4s {
		go solver.routine_row4(index1, index2, index3, index4)
	}
}

func (solver *Solver) routine_row4(index1 int, index2 int, index3 int, index4 int) {
	for index5 := range solver.row5s {
		go solver.routine_row5(index1, index2, index3, index4, index5)
	}
}

func (solver *Solver) routine_row5(index1 int, index2 int, index3 int, index4 int, index5 int) {
	for index6 := range solver.row6s {
		go solver.routine_row6(index1, index2, index3, index4, index5, index6)
	}
}

func (solver *Solver) routine_row6(index1 int, index2 int, index3 int, index4 int, index5 int, index6 int) {
	for index7 := range solver.row7s {
		go solver.routine_row7(index1, index2, index3, index4, index5, index6, index7)
	}
}

func (solver *Solver) routine_row7(index1 int, index2 int, index3 int, index4 int, index5 int, index6 int, index7 int) {
	for index8 := range solver.row8s {
		go solver.routine_row8(index1, index2, index3, index4, index5, index6, index7, index8)
	}
}

func (solver *Solver) routine_row8(index1 int, index2 int, index3 int, index4 int, index5 int, index6 int, index7 int, index8 int) {
	for index9 := range solver.row9s {
		go solver.routine_row9(index1, index2, index3, index4, index5, index6, index7, index8, index9)
	}
}

func (solver *Solver) routine_row9(index1 int, index2 int, index3 int, index4 int, index5 int, index6 int, index7 int, index8 int, index9 int) {
	go solver.routine_validator(index1, index2, index3, index4, index5, index6, index7, index8, index9)
}

// blocks.go
func (solver *Solver) generate_blocks() []int {

	var blocks []int
	decvals := [9]int{49, 50, 51, 52, 53, 54, 55, 56, 57}

	for counter := 123456789; counter <= 987654321; counter++ {

		// Convert number to string ([]byte)
		digits := strconv.Itoa(counter)

		// Check if every number is only represented only once
		var valid bool
		valid = true
		for decval := range decvals {
			var count int
			for digit := range digits {
				if digits[digit] == byte(decvals[decval]) {
					count = count + 1
				}
			}

			if count != 1 {
				valid = false
			}
		}

		if valid {
			blocks = append(blocks, counter)
		}
	}

	return blocks

}

// stash.go
func (solver *Solver) print_block(block int) {
	digits := strconv.Itoa(block)
	fmt.Printf("%c %c %c\n%c %c %c\n%c %c %c\n\n", digits[0], digits[1], digits[2], digits[3], digits[4], digits[5], digits[6], digits[7], digits[8])
}