package main

import (
	"fmt"
	"strconv"
	"strings"
)

func getSumCarry(a int, b int, c int) (int, int) {
	if a+b+c < 10 {
		return a + b + c, 0
	}
	return (a + b + c) - 10, 1
}

type List struct {
	val  int
	len  int
	next *List
}

func (l *List) num2list(num int) *List {
	sNum := strings.Split(fmt.Sprintf("%d", num), "")

	val, _ := strconv.Atoi(sNum[len(sNum)-1])
	l = &List{val: val, len: 0, next: nil}

	for id := len(sNum) - 2; id >= 0; id -- {
		val, _ = strconv.Atoi(sNum[id])

		for lst := l; lst != nil; lst = lst.next {
			if lst.next == nil {
				l.len ++
				lst.next = &List{val: val, len: l.len, next: nil}
				break
			}
		}
	}
	return l
}

func allign(a *List, b *List) {
	longest := 0
	adjust := a
	if a.len > b.len {
		longest = a.len
		adjust = b
	} else if b.len > a.len {
		longest = b.len
	} else {
		return
	}

	for i := longest; i >= 0; i -- {
		for lst := adjust; lst != nil; lst = lst.next {
			if lst.next == nil {
				adjust.len ++
				lst.next = &List{val: 0, len: adjust.len, next: nil}
				break
			}
		}
	}

	return
}

func sumList(a *List, b *List) *List {
	carry := 0
	aNext := a
	bNext := b

	for i := a.len; i >= 0; i -- {
		bNext.val, carry = getSumCarry(aNext.val, bNext.val, carry)
		bNext = bNext.next
		aNext = aNext.next
	}

	return b
}

func main() {
	LList := List{}
	first := LList.num2list(342)
	secnd := LList.num2list(465)

	result := sumList(first, secnd)
	fmt.Println(result.val, result.next.val, result.next.next.val)

	f := LList.num2list(199)
	s := LList.num2list(1)

	allign(f, s)

	result = sumList(f, s)
	fmt.Println(result.val, result.next.val, result.next.next.val)

}