vedesh-padal

class Solution {

    // INTUITION:
        // to get the min. height, find the diameter of the graph (tree)
        // the middle node is your root of the min. height tree
        // if diameter of tree is of length:
            // odd: middle node in the diameter path is the only root node 
            //      that is possible that forms the min. tree hight
            // even: there are two root nodes possible that form the min. tree height

vedesh-padal

class RangeFreqQuery {
    private int[] arr;
    private Map<Integer, Integer>[] segTree;

    public RangeFreqQuery(int[] arr) {
        this.arr = arr;
        segTree = new HashMap[4*arr.length];

        buildSegTree(0, 0, arr.length - 1, arr, segTree);
    }

vedesh-padal

// Alice has some number of cards and she wants to rearrange the cards into
// groups so that each group is of size groupSize, and consists of groupSize
// consecutive cards.

// Given an integer array hand where hand[i] is the value written on the ith
// card and an integer groupSize, return true if she can rearrange the cards, or
// false otherwise.

// Example 1:
// Input: hand = [1,2,3,6,2,3,4,7,8], groupSize = 3