0445. Add Two Numbers I I

题目 #

You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

Follow up: What if you cannot modify the input lists? In other words, reversing the lists is not allowed.

Example:

``````
Input: (7 -> 2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 8 -> 0 -> 7

``````

代码 #

``````
package leetcode

/**
* type ListNode struct {
*     Val int
*     Next *ListNode
* }
*/
package leetcode

import (
"github.com/halfrost/leetcode-go/structures"
)

// ListNode define
type ListNode = structures.ListNode

/**
* type ListNode struct {
*     Val int
*     Next *ListNode
* }
*/
func addTwoNumbers445(l1 *ListNode, l2 *ListNode) *ListNode {
if l1 == nil {
return l2
}
if l2 == nil {
return l1
}
l1Length := getLength(l1)
l2Length := getLength(l2)
newHeader := &ListNode{Val: 1, Next: nil}
if l1Length < l2Length {
} else {
}
}
}

func addNode(l1 *ListNode, l2 *ListNode, offset int) *ListNode {
if l1 == nil {
return nil
}
var (
res, node *ListNode
)
if offset == 0 {
res = &ListNode{Val: l1.Val + l2.Val, Next: nil}
} else {
res = &ListNode{Val: l1.Val, Next: nil}
}
if node != nil && node.Val > 9 {
res.Val++
node.Val = node.Val % 10
}
res.Next = node
return res
}

func getLength(l *ListNode) int {
count := 0
cur := l
for cur != nil {
count++
cur = cur.Next
}
return count
}

func addTwoNumbers1(l1 *ListNode, l2 *ListNode) *ListNode {
reservedL1 := reverseList(l1)
reservedL2 := reverseList(l2)

carry := 0
for reservedL1 != nil || reservedL2 != nil || carry > 0 {
val := carry
if reservedL1 != nil {
val = reservedL1.Val + val
reservedL1 = reservedL1.Next
}
if reservedL2 != nil {
val = reservedL2.Val + val
reservedL2 = reservedL2.Next
}
carry = val / 10
head.Next = &ListNode{Val: val % 10}
}
}

var prev *ListNode

}
return prev
}

func addTwoNumbers(l1 *ListNode, l2 *ListNode) *ListNode {
stack1 := pushStack(l1)
stack2 := pushStack(l2)

carry := 0
for len(stack1) > 0 || len(stack2) > 0 || carry > 0 {
val := carry
if len(stack1) > 0 {
val = val + stack1[len(stack1)-1]
stack1 = stack1[:len(stack1)-1]
}
if len(stack2) > 0 {
val = val + stack2[len(stack2)-1]
stack2 = stack2[:len(stack2)-1]
}
carry = val / 10
head.Next = &ListNode{Val: val % 10, Next: tmp}
}
}

func pushStack(l *ListNode) []int {
var stack []int
for l != nil {
stack = append(stack, l.Val)
l = l.Next
}
return stack
}

``````

Apr 8, 2023