Array DSA problems in swift.
[Question]: Find maximum sum of a subarray of size k example [9,1,3,2,6,1,5,9], k: 4 = output: 21 (6+1+5+9)Solution: with sliding window we can achieve. first we take sum of first k elements further move elements by 1 window size & add the latest var & remove last var.
[Question]: Given an integer array that may contain duplicates, find all possible subsets (the power set). No duplicates allowed in answer. Solution in any order allowed. Input: nums = [1,2,3] Output: [1,2,3] [1,2] [1,3] [1] [2,3] [2] [3] [] Approach #2: Using Bitwise OperatorQuestion: Power Set: Print all the possible subsequences of the String To check …
[Question ] Check weather array is palindrome Example : [1,2,2,1] ===> It’s palindrome Solution#: Here we are checking first & last element equality & increase till mid of array
# Question 1: Find sum of first n numbers. Example :– n = 3 => 3+2+1 =6. We will use recursion to solve this problem. # Question 2: Find sum of array elements using recursion approach :
[Question] In a given array return true if array have duplicate elements . For example 1 :[1,2,3,1] = True example 1 :[1,2,3,] = False So here we have used Dictionary which is Hashable which contains only unique keys hence we can find duplicates elements in swift.
[Question] Find Maximum and minimum of an array in swift using minimum number of comparisons #Approach: 1 Use first element as min max & start loop from second element onwards & return tuple of the min max number
[Question]: Reverse a string with O(1) extra memory. The input string is given as an array of characters like [“C”, “A”, “R”] So here we have used one for loop which iterates half of array & swapping last with first
[Link] In Pascal’s triangle, each element is the sum of the two numbers directly above it.
Question: – if on given matrix any element is zero set entire row & column to zero [Link] Approach #2 Here we find the rows & cols which is zero & then iterate over matrix & make that rows and cols as zero
