My Own Notes

Sort a linked list in  O ( n  log  n ) time using constant space complexity. Solution As we are sorted a linked list, we need that our al...

Given a 2D board containing  'X'  and  'O' , capture all regions surrounded by  'X' . A region is captured by fli...

Given a singly linked list L : L 0 → L 1 →…→ L n -1 → L n , reorder it to: L 0 → L n → L 1 → L n -1 → L 2 → L n -2 →… You must do this i...

There are  N  children standing in a line. Each child is assigned a rating value. You are giving candies to these children subjected to t...

Given a set of distinct integers,  S , return all possible subsets. Note: Elements in a subset must be in non-descending order. The so...

Given a matrix of  m  x  n  elements ( m  rows,  n  columns), return all elements of the matrix in spiral order. For example, Given the f...

Given an array of integers, every element appears three times except for one. Find that single one. Note: Your algorithm should have a...