Hamid Oyempemi Oyedee

Hexadecimal color code for transparency

For example, you want to set 40% alpha transparence to #000000 (black color), you need to add 66 like this #66000000.

	//Counting Bits - Bit manipulation

	// Given an integer n, return an array ans of length n + 1 such that for each i (0 <= i <= n), ans[i] is the number of 1's in the binary representation of i.

	// Example 1:

	// Input: n = 2
	// Output: [0,1,1]
	// Explanation:
	// 0 --> 0

	//Question 7 - Dynamic programming

	// Given an integer array nums, handle multiple queries of the following type:

	// Calculate the sum of the elements of nums between indices left and right inclusive where left <= right.
	// Implement the NumArray class:

	// NumArray(int[] nums) Initializes the object with the integer array nums.
	// int sumRange(int left, int right) Returns the sum of the elements of nums between indices left and right inclusive (i.e. nums[left] + nums[left + 1] + ... + nums[right]).

	// Question 1:
	// Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.

	// Example 1:

	// Input: nums = [1,2,3,1]
	// Output: true
	// Example 2:

	// Input: nums = [1,2,3,4]

	//Problem 6

	/*
	You are given an array prices where prices[i] is the price of a given stock on the ith 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:

	void main() {
	final solution = Solution();
	String s = "abcabcbb";
	final result = solution.lengthOfLongestSubstring(s);
	print(result);
	}

	/*
	* Given a string s, find the length of the longest substring without repeating characters.

	void main() {
	final solution = Solution();

	final result = solution.climbStairs(5);
	print(result);
	}

	/*
	*
	You are climbing a staircase. It takes n steps to reach the top.

	void main() {
	final solution = Solution();
	List<int> nums = [4, 1, 2, 1, 2];

	final result = solution.singleNumber(nums);
	print(result);
	}

	/*
	Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.

	void main() {
	final solution = Solution();
	List<int> nums = [1,1];

	final result = solution.findDisappearedNumbers(nums);
	print(result);
	}

	//Given an array nums of n integers where nums[i] is in the range [1, n], return an array of all the integers in the range [1, n] that do not appear in nums.

	/*
	Given an array nums containing n distinct numbers in the range [0, n], return the only number in the range that is missing from the array.

	Example 1:

	Input: nums = [3,0,1]
	Output: 2
	Explanation: n = 3 since there are 3 numbers, so all numbers are in the range [0,3]. 2 is the missing number in the range since it does not appear in nums.
	Example 2: