DSA

  121. Best Time to Buy and Sell Stock You are given an array   prices   where   prices[i]   is the price of a given stock on the   i th   day. You want to maximize your profit by choosing a  single day  to buy one stock and choosing a  different day in the future  to sell that stock. Return  the maximum profit you can achieve from this transaction . If you cannot achieve any profit, return  0 .   Example 1: Input: prices = [7,1,5,3,6,4] Output: 5 Explanation: Buy on day 2 (price = 1) and sell on day 5 (price = 6), profit = 6-1 = 5. Note that buying on day 2 and selling on day 1 is not allowed because you must buy before you sell. Example 2: Input: prices = [7,6,4,3,1] Output: 0 Explanation: In this case, no transactions are done and the max profit = 0. wrong approach class Solution :     def maxProfit ( self , prices : List[ int ]) -> int :         minprices= min (prices) ...

  26. Remove Duplicates from Sorted Array Given an integer array  nums  sorted in  non-decreasing order , remove the duplicates  in-place  such that each unique element appears only  once . The  relative order  of the elements should be kept the  same . Then return  the number of unique elements in  nums . Consider the number of unique elements of  nums  to be  k , to get accepted, you need to do the following things: Change the array  nums  such that the first  k  elements of  nums  contain the unique elements in the order they were present in  nums  initially. The remaining elements of  nums  are not important as well as the size of  nums . Return  k . Custom Judge: The judge will test your solution with the following code: int[] nums = [...]; // Input array int[] expectedNums = [...]; // The expected answer with correct length int k = removeDuplicate...