Just programming

LeetCode 271: Encode and Decode String   Design an algorithm to encode   a list of strings   to   a string . The encoded string is then sent over the network and is decoded back to the original list of strings. Implement the  encode  and  decode  methods. You are not allowed to solve the problem using any serialize methods (such as  eval ). Example 1: Input: dummy_input = ["Hello","World"] Output: ["Hello","World"] Explanation: Machine 1: Codec encoder = new Codec(); String msg = encoder.encode(strs); Machine 1 ---msg---> Machine 2 Machine 2: Codec decoder = new Codec(); String[] strs = decoder.decode(msg); Example 2: Input: dummy_input = [""] Output: [""] Solution: Decided to use => len(str) + "#" + str as encoding public class Codec { public String encode ( List < String > strs ) { String ans = "" ; for ( int i = 0 ; i < strs . size (); i++) { ...

  Differences Between Combination Sum1, Combination Sum2 and Combination Sum 3 Leetcode has 4 types of Cobination Sum Problems. We should know the similarities and differences among all those problems:- https://leetcode.com/problems/combination-sum/ https://leetcode.com/problems/combination-sum-ii/description/ https://leetcode.com/problems/combination-sum-iii/