index.js

/**
 * Returns a boolean representing whether or not all values are numbers.
 * @param {number[]} rolls - An array of numbers representing rolls on a die.
 * @returns {boolean} Returns `true` if all values in the array are numbers. Otherwise, return `false`.
 */
function isValid(rolls) {
  let result = true;
  for (i = 0; i < rolls.length; i++) {
    if (typeof rolls[i] !== 'number') {
      result = false
    }
  } return result;
}

/**
 * Finds a value in an array. If that value is in the array, returns it. Otherwise, returns `null`.
 * @param {number[]} rolls - An array of numbers representing rolls on a die.
 * @param {number} value - A specific value to find.
 * @returns {*} - The found value or `null`.
 */
function findValue(rolls, value) {
  for (i = 0; i < rolls.length; i++) {
    if (rolls[i] === value) {
      return value;
    }
  }
  return null
}

/**
 * Returns a new array from the `rolls` array with only values equal to or greater than the `lowest` value.
 * @param {number[]} rolls - An array of numbers representing rolls on a die.
 * @param {number} lowest - A number that represents the lowest allowed value in the new array.
 * @returns {number[]} An array of all numbers that are equal to or higher than the `lowest` value.
 */
function filterOutLowValues(rolls, lowest) {
  let newArray = [];
  for (i = 0; i < rolls.length; i++) {
    if (rolls[i] >= lowest) {
      newArray.push(rolls[i]);
    }
  }
  return newArray;
}

/**
 * Returns an object which has rolls as keys and counts as values.
 * @param {number[]} rolls - An array of numbers representing rolls on a die.
 * @returns {object} An object where the keys are numbers rolled and the values are the number of times that roll appears in the `rolls` array.
 */
function getRollCounts(rolls) {
  let newObject = {};
  for (i = 0; i < rolls.length; i++) {
    if (newObject[rolls[i]] === undefined) {
      newObject[rolls[i]] = 1;
    } else {
      newObject[rolls[i]] += 1
    }
  }
return newObject
}

// Do not change the code below here.
module.exports = {
  isValid,
  findValue,
  filterOutLowValues,
  getRollCounts,
};