Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating letters for “abcabcbb” is “abc”, which the length is 3. For “bbbbb” the longest substring is “b”, with the length of 1.
You are given two linked lists representing two non-negative numbers. 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.
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
Given an array of integers, find two numbers such that they add up to a specific target number.
The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note that your returned answers (both index1 and index2) are not zero-based.
You may assume that each input would have exactly one solution.
Input: numbers={2, 7, 11, 15}, target=9
Output: index1=1, index2=2
A snail in a well can climbs 3 meters up in the day, and slide 2 meters down at the night. Given the height of the well h, how many days does it take for the snail to climb out of the well?
Let a pair of distinct positive integers, (i, j), be considered “scrambled” if you can obtain j by reordering the digits of i. For example, (12345, 25341) is a scrambled pair, but (12345, 67890) is not.
Given integers A and B with the same number of digits and no leading zeroes, how many distinct scrambled pairs (i, j) are there that satisfy: A <= i < j <= B?