Counting Numbers Having Its Consecutive Num

https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/528/week-1/3289/

>> Solution 1 :

O(n) time, O(n) space complexity

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Moving Zeroes To The End in Integer Array

>> Solution 1:

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>> Solution 2 :

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Finding Maximum Sum of Sub Array

https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/528/week-1/3285/

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Happy Number Check

Write an algorithm to determine if a number n is "happy".  A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.  Return True if n is a happy number, and False if not.

https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/528/week-1/3284/

>> Solution 1

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Link List Middle Node

https://leetcode.com/explore/challenge/card/30-day-leetcoding-challenge/529/week-2/3290/

>> Solution 1 : Find Size, Then Middle

O(n) time, O(1) space


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>> Solution 2 : Slow and Fast Pointer

O(n) time, O(1) space

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