easy-wallpaper.js

// STEPS to solve a problem:
// 1. define what are the input variables
// 2. what is the output format or the result
// 3. define what constants are in the problem?
// 3. (not always) Find the solution the real world if you had to give these instruction to a group of kids
// 4. Reverse engineer the ouput from input

// INPUT variables for the room size
// l = number, lenght of the room in m
// h = number, height of the room in m 
// w = number, width of the room in m

// OUTPUT of the function
// return string = number of rools the user must buy
 
function wallpaper(l, w, h) {
  const numbers = ["zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "eleven", "twelve","thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen", "twenty"];
 
  if(l==0 || w==0 || h== 0) return numbers[0];
  
  // extra length to buy 
  const percentageToBuy = 1.15; //100% + 15%
  const widthRolls = 0.52; //m or 52cm
  const lengthRolls = 10; //m
  
  const sizeRoom = (2* w*h) + (2* l*h);
  
  const sizeRoll = widthRolls*lengthRolls;
  
  const rolls = Math.ceil((sizeRoom / sizeRoll) * percentageToBuy);
  if(rolls > 20) rolls = 20;
  
  return numbers[rolls];
}