You are given a string word. The word is considered valid if it satisfies the following conditions:
Return true if the word is valid, otherwise return false.
s and t, where every character occurs at most once in both strings and t is a permutation of s. The permutation difference between s and t is defined as the sum of the absolute differences between the index of each character in s and the index of the occurrence of the same character in t. Your task is to compute the permutation difference between s and t.nums1 and nums2 of lengths n and m respectively, and a positive integer k. A pair (i, j) is called good if nums1[i] is divisible by nums2[j] * k (0 <= i <= n - 1, 0 <= j <= m - 1). Your task is to return the total number of good pairs.s representing a sequence of events where each character is either ‘E’ (a person enters the waiting room) or ‘L’ (a person leaves the waiting room). The waiting room starts empty. Simulate the events and determine the minimum number of chairs required to ensure there is always a chair available for every person who enters the room.n and k. There are n children numbered from 0 to n - 1, standing in a queue from left to right. Initially, child 0 holds a ball and the direction of passing the ball is towards the right. After each second, the child holding the ball passes it to the next child in the queue. If the ball reaches the first or last child, the direction of passing the ball reverses. You need to determine which child will have the ball after k seconds.nums. In each operation, you can either add or subtract 1 from any element in nums. Your task is to determine the minimum number of operations required to make all elements of nums divisible by 3.