The longest common subsequence (LCS) problem is the problem of finding the longest subsequence common to all sequences in a set of sequences (often just two sequences). Analysis Let dp[i+1][j+1] be the length of the longest common subsequence of string a & b, when a[i] and b[j] are compared to each other. (0
Given an integer, write a function to determine if it is a power of three. Java Solution 1 – Iteration public boolean isPowerOfThree(int n) { if(n==1) return true; boolean result = false; while(n>0){ int m = n%3; if(m==0){ n=n/3; if(n==1) return true; }else{ return false; } } return result; }public boolean isPowerOfThree(int … Read more
Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. Java Solution public int trailingZeroes(int n) { if (n < 0) return -1; int count = 0; for (long i = 5; n / i >= 1; i *= 5) { count += … Read more
Problem Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the next smallest number in the BST. Note: next() and hasNext() should run in average O(1) time and uses O(h) memory, where h is the height of the tree. … Read more