Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example:

Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].

Given an array of integers, find all subsets of the array with 3 values where the 3 values sum up to a target number.

Note: The solution subsets must not contain duplicate triplets.

For example, given the array [-1, 0, 1, 2, -1, -4], and the target 0: The solution set is: [[-1, 0, 1], [-1, -1, 2]] // The two -1 values in the array are considered to be distinct

There are 2 key procedures in solving this algorithm. Sorting the array, and avoiding duplicates.

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order 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.

Example:

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4) Output: 7 -> 0 -> 8 Explanation: 342 + 465 = 807.

Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements.

Example:

Input: [0,1,0,3,12] Output: [1,3,12,0,0]

Note:

You must do this in-place without making a copy of the array. Minimize the total number of operations.

Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.

Example 1:

Input: 121 Output: true

Example 2:

Input: -121 Output: false Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.