/**
* Lock by Leetcode
* 369. Plus One Linked List
* https://www.lintcode.com/problem/plus-one-linked-list/description
*
* Given a non-negative integer represented as non-empty a singly linked list of digits, plus one to the integer.
You may assume the integer do not contain any leading zero, except the number 0 itself.
The digits are stored such that the most significant digit is at the head of the list.
Example
Given head = 1 -> 2 -> 3 -> null, return 1 -> 2 -> 4 -> null.
*/
/**
* @param head: the first Node
* @return: the answer after plus one
*/
const plusOne = function (head) {
let str = "";
while (head != null) {
str += head.val;
head = head.next;
}
let resultStr = addTwoString(str, "1");
let arr = resultStr.split("");
let newHead = new ListNode(parseInt(arr[0]));
createList(newHead, 1, arr);
return newHead;
};
var addTwoString = function (str1, str2) {
let len1 = str1.length - 1, len2 = str2.length - 1;
let carry = 0;
let res = [];
while (len1 >= 0 || len2 >= 0) {
let a = len1 >= 0 ? str1.charAt(len1--) - '0' : 0;
let b = len2 >= 0 ? str2.charAt(len2--) - '0' : 0;
let temp = a + b + carry;
if (temp >= 10) {
carry = Math.floor(temp / 10);//10位
temp = Math.floor(temp % 10);//个位
} else
carry = 0;
res.unshift(temp);
}
if (carry)
res.unshift(1);
return res.join("");
};
var createList = function (head, index, arr) {
if (index >= arr.length)
return;
let node = new ListNode(parseInt(arr[index]));
head.next = node;
createList(node, index + 1, arr.concat());
};