kkchu791

# Raindrops

Convert a number to a string, the contents of which depend on the number's factors.

- If the number has 3 as a factor, output 'Pling'.
- If the number has 5 as a factor, output 'Plang'.
- If the number has 7 as a factor, output 'Plong'.
- If the number does not have 3, 5, or 7 as a factor,
  just pass the number's digits straight through.

kkchu791

README

Backend App - Auction

Demo: https://robot-auction.herokuapp.com/

Info

ruby '2.6.3'

kkchu791

ass TreeNode
  attr_accessor :value, :left, :right

  def initialize(value)
    @value = value
  end
end

tree = TreeNode.new(5)
tree.left = TreeNode.new(3)

kkchu791

var minCostClimbingStairs = function(cost) {
    for (let i = 2; i < cost.length; i++) {
        cost[i] += Math.min(cost[i-1], cost[i-2]);
    }
    
    return Math.min(cost[cost.length-1], cost[cost.length-2]);
};

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var rob = function(nums) {
}

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var rob = function(nums) {
    var prevEvenMax = 0;
    var prevOddMax = 0;
    
    for (var i = 0; i < nums.length; i++) {
        if (i % 2 === 0) {
            prevEvenMax = Math.max(prevEvenMax + nums[i], prevOddMax);
        }
        else {
            prevOddMax = Math.max(prevEvenMax, prevOddMax + nums[i]);

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var rob = function(profits) {
    let prevMaxProfit = 0;
    let currMaxProfit = 0;
    
    for (let i = 0; i < profits.length; i++) {
        const prevPlusProfit = prevMaxProfit + profits[i];
        prevMaxProfit = currMaxProfit;
        currMaxProfit = Math.max(currMaxProfit, prevPlusProfit);
    }
    

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// Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.

// Example:

// Input: [-2,1,-3,4,-1,2,1,-5,4],
// Output: 6
// Explanation: [4,-1,2,1] has the largest sum = 6.
// Follow up:

// If you have figured out the O(n) solution, try coding another solution using the divide and conquer approach, which is more subtle.

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// Given an array of integers A sorted in non-decreasing order, 
// return an array of the squares of each number, also in sorted non-decreasing order.

// array = [-4,-1,0,3,10]

const sortedSquares = (array) => {
    // square the elements in the array
    const squaredArray = array.map(el => el * el);

    // use insertion sort to sort the array from min to max

kkchu791

# nums = [2, 3, 11, 22], target = 9,
# Because nums[0] + nums[1] = 2 + 7 = 9,
#return [0, 1]

def two_sum(nums, target)
  nums.each do |i|
    nums.each do |x|
      if i + x == target && nums.index(i) != nums.index(x)
        return [nums.index(i), nums.index(x)]
      end