Finding the longest Palindrome substring is a classic problem of coding interview. Inthis post, I will summarize 3 different solutions for this problem. 3.1 Naive Approach Naively, we can simply examine every substring and check if it is palindromic. Thetime complexity is O(nˆ3). If this is submitted to LeetCode online Read more…
The problem: Evaluate the value of an arithmetic expression in Reverse Polish Notation.Valid operators are +, -, , /. Each operand may be an integer or another expression. Some examples: [“2”, “1”, “+”, “3”, ““] -> ((2 + 1) * 3) -> 9[“4”, “13”, “5”, “/”, “+”] -> (4 + Read more…
Problem: Rotate an array of n elements to the right by k steps. For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4]. How many different ways do you know to solve this problem? 1.1 Solution 1 – Intermediate Array In a straightforward Read more…