diff --git a/src/functions-and-arrays.js b/src/functions-and-arrays.js index 3a7dbec41..7213be10f 100644 --- a/src/functions-and-arrays.js +++ b/src/functions-and-arrays.js @@ -1,119 +1,465 @@ // Iteration #1: Find the maximum -function maxOfTwoNumbers() {} - - +function maxOfTwoNumbers(num1, num2) { + return Math.max(num1, num2); +} // Iteration #2: Find longest word -const words = ['mystery', 'brother', 'aviator', 'crocodile', 'pearl', 'orchard', 'crackpot']; - -function findLongestWord() {} - +const words = [ + "mystery", + "brother", + "aviator", + "crocodile", + "pearl", + "orchard", + "crackpot", +]; +function findLongestWord(wordArray) { + if (wordArray.length === 0) { + return null; + } else if (wordArray.length === 1) { + return wordArray[0]; + } else if (wordArray.length === 2) { + if (wordArray[0].length == wordArray[1].length) { + return wordArray[0]; + } + } else { + let longestWord = wordArray[0]; + for (i = 1; i < wordArray.length; i++) { + if (wordArray[i].length > longestWord.length) { + longestWord = wordArray[i]; + } + } + return longestWord; + } +} // Iteration #3: Calculate the sum const numbers = [6, 12, 1, 18, 13, 16, 2, 1, 8, 10]; -function sumNumbers() {} - - +function sumNumbers(numbers) { + if (numbers.length === 0) { + return 0; + } else if (numbers.length == 1) { + return numbers[0]; + } else { + // return zero if all elements are zero + let isZero = false; + for (let i = 0; i < numbers.length; i++) { + if (numbers[i] === 0) { + isZero = true; + } else { + isZero = false; + break; + } + } + if (isZero) { + return 0; + } else { + let sum = 0; + for (i = 0; i < numbers.length; i++) { + sum += numbers[i]; + } + return sum; + } + } +} // Iteration #3.1 Bonus: -function sum() {} - - +function sum(array) { + let sum = 0; + // For each element in the array, do a switch case + array.forEach((element) => { + switch (typeof element) { + case "object": + throw new Error("Function cannot take objects as arguments"); + case "number": + sum += element; + break; + case "string": + sum += element.length; + break; + case "boolean": + if (element) { + sum += 1; + } + break; + default: + // do nothing if any other typeof contingency + break; + } + }); + return sum; +} // Iteration #4: Calculate the average // Level 1: Array of numbers const numbersAvg = [2, 6, 9, 10, 7, 4, 1, 9]; -function averageNumbers() {} - +function averageNumbers(numbers) { + if (numbers.length == 0) { + return null; + } else if (numbers.length === 1) { + return numbers[0]; + } else { + let sum = 0; + for (let i = 0; i < numbers.length; i++) { + sum += numbers[i]; + } + return sum / numbers.length; + } +} // Level 2: Array of strings -const wordsArr = ['seat', 'correspond', 'linen', 'motif', 'hole', 'smell', 'smart', 'chaos', 'fuel', 'palace']; +const wordsArr = [ + "seat", + "correspond", + "linen", + "motif", + "hole", + "smell", + "smart", + "chaos", + "fuel", + "palace", +]; -function averageWordLength() { } +function averageWordLength(wordArray) { + if (wordArray.length == 0) { + return null; + } else if (wordArray.length === 1) { + return wordArray[0].length; + } else { + let sum = 0; + for (let i = 0; i < wordArray.length; i++) { + sum += wordArray[i].length; + } + return sum / wordArray.length; + } +} // Bonus - Iteration #4.1 -function avg() {} +function avg(array) { + if (array.length === 0) return null; + let sum = 0; + array.forEach((element) => { + switch (typeof element) { + case "object": + throw new Error("Function cannot take objects as arguments"); + case "number": + sum += element; + break; + case "string": + sum += element.length; + break; + case "boolean": + if (element) { + sum += 1; + } + break; + default: + // do nothing if any other typeof contingency + break; + } + }); + return sum / array.length; +} // Iteration #5: Unique arrays const wordsUnique = [ - 'crab', - 'poison', - 'contagious', - 'simple', - 'bring', - 'sharp', - 'playground', - 'poison', - 'communion', - 'simple', - 'bring' + "crab", + "poison", + "contagious", + "simple", + "bring", + "sharp", + "playground", + "poison", + "communion", + "simple", + "bring", ]; -function uniquifyArray() {} +function uniquifyArray(wordsArray) { + if (wordsArray.length == 0) { + return null; + } + const uniquifiedArray = []; + for (let i = 0; i < wordsArray.length; i++) { + const word = wordsArray[i]; + if (uniquifiedArray.indexOf(word) === -1) { + uniquifiedArray.push(word); + } + } + return uniquifiedArray; +} // Iteration #6: Find elements -const wordsFind = ['machine', 'subset', 'trouble', 'starting', 'matter', 'eating', 'truth', 'disobedience']; - -function doesWordExist() {} - +const wordsFind = [ + "machine", + "subset", + "trouble", + "starting", + "matter", + "eating", + "truth", + "disobedience", +]; +function doesWordExist(wordsToEvaluate, wordToFind) { + if (wordsToEvaluate.length == 0) { + return null; + } else if ( + wordToFind === wordsToEvaluate[0] && + wordsToEvaluate.length === 1 + ) { + return true; + } else { + if (wordsToEvaluate.indexOf(wordToFind) === -1) { + return false; + //Could also be modified to: else {return true} + } else if (wordsToEvaluate.indexOf(wordToFind) !== -1) { + return true; + } + } +} // Iteration #7: Count repetition const wordsCount = [ - 'machine', - 'matter', - 'subset', - 'trouble', - 'starting', - 'matter', - 'eating', - 'matter', - 'truth', - 'disobedience', - 'matter' + "machine", + "matter", + "subset", + "trouble", + "starting", + "matter", + "eating", + "matter", + "truth", + "disobedience", + "matter", ]; -function howManyTimes() {} - - +function howManyTimes(wordArray, wordToSearch) { + if (wordArray.length == 0) { + return 0; + } else { + i = 0; + count = 0; + while (i < wordArray.length) { + if (wordArray[i] === wordToSearch) { + count++; + } + i++; + } + return count; + } +} // Iteration #8: Bonus const matrix = [ [8, 2, 22, 97, 38, 15, 0, 40, 0, 75, 4, 5, 7, 78, 52, 12, 50, 77, 91, 8], - [49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 4, 56, 62, 0], - [81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 3, 49, 13, 36, 65], + [ + 49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 4, 56, 62, + 0, + ], + [ + 81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 3, 49, 13, 36, + 65, + ], [52, 70, 95, 23, 4, 60, 11, 42, 69, 24, 68, 56, 1, 32, 56, 71, 37, 2, 36, 91], - [22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80], - [24, 47, 32, 60, 99, 3, 45, 2, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50], - [32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70], - [67, 26, 20, 68, 2, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, 21], - [24, 55, 58, 5, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72], + [ + 22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, + 80, + ], + [ + 24, 47, 32, 60, 99, 3, 45, 2, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, + 50, + ], + [ + 32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, + 70, + ], + [ + 67, 26, 20, 68, 2, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, + 21, + ], + [ + 24, 55, 58, 5, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, + 72, + ], [21, 36, 23, 9, 75, 0, 76, 44, 20, 45, 35, 14, 0, 61, 33, 97, 34, 31, 33, 95], [78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 3, 80, 4, 62, 16, 14, 9, 53, 56, 92], - [16, 39, 5, 42, 96, 35, 31, 47, 55, 58, 88, 24, 0, 17, 54, 24, 36, 29, 85, 57], + [ + 16, 39, 5, 42, 96, 35, 31, 47, 55, 58, 88, 24, 0, 17, 54, 24, 36, 29, 85, + 57, + ], [86, 56, 0, 48, 35, 71, 89, 7, 5, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58], - [19, 80, 81, 68, 5, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 4, 89, 55, 40], + [ + 19, 80, 81, 68, 5, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 4, 89, 55, + 40, + ], [4, 52, 8, 83, 97, 35, 99, 16, 7, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66], - [88, 36, 68, 87, 57, 62, 20, 72, 3, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69], - [4, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, 36], - [20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 4, 36, 16], - [20, 73, 35, 29, 78, 31, 90, 1, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 5, 54], - [1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, 48] + [ + 88, 36, 68, 87, 57, 62, 20, 72, 3, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, + 69, + ], + [ + 4, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, + 36, + ], + [ + 20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 4, 36, + 16, + ], + [ + 20, 73, 35, 29, 78, 31, 90, 1, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 5, + 54, + ], + [ + 1, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 1, 89, 19, 67, + 48, + ], ]; -function greatestProduct() {} - - +function greatestProduct(matrix) { + let i = 0; + let j; + let currentProduct = 0; + let biggestProduct = 0; + let numFactors = 4; + + // Check if all elements are 1 or 2 with arrow function on a flat matrix + let flatMatrix = matrix.flat(); + let isAllOne = flatMatrix.every((element) => element === 1); + let isAllTwo = flatMatrix.every((element) => element === 2); + + // Exit function in case of all ones or all twos + if (isAllOne || isAllTwo) { + isAllOne ? (sum = 1) : (sum = 16); + return sum; + } + + // Iterations in each row so that j+3 is not out of bounds + let maxIterations = matrix[0].length - numFactors; + + for (i; i < matrix.length; i++) { + j = 0; + for (j; j <= maxIterations; j++) { + currentProduct = + matrix[i][j] * matrix[i][j + 1] * matrix[i][j + 2] * matrix[i][j + 3]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + } + } + + i = 0; + // Iterations in each row so that j+3 is not out of bounds + maxIterations = matrix.length - numFactors; + + // Compare biggestProduct with matrix column products + for (i; i < matrix[0].length; i++) { + j = 0; + for (j; j <= maxIterations; j++) { + currentProduct = + matrix[j][i] * matrix[j + 1][i] * matrix[j + 2][i] * matrix[j + 3][i]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + } + } + + return biggestProduct; +} +function greatestProductOfDiagonals(matrix) { + let i = 0; + let j; + let currentProduct = 0; + let biggestProduct = 0; + let maxIterationsRow; + let maxIterationsCol; + let numFactors = 4; + + // Iterations in each row and columns to allow for diagonal length + maxIterationsRow = matrix.length - numFactors; + maxIterationsCol = matrix[0].length - numFactors; + + // Forward slash diagonal product comparison + for (i; i <= maxIterationsRow; i++) { + j = 0; + for (j; j <= maxIterationsCol; j++) { + currentProduct = + matrix[i][j] * + matrix[i + 1][j + 1] * + matrix[i + 2][j + 2] * + matrix[i + 3][j + 3]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + // if there is space for more multiplications along same diagonal, keep going + if (i <= maxIterationsRow) { + let k = i + 1; + let l = j + 1; + while (k <= maxIterationsRow) { + currentProduct = + matrix[k][l] * + matrix[k + 1][l + 1] * + matrix[k + 2][l + 2] * + matrix[k + 3][l + 3]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + l++; + k++; + } + } + } + } + + i = 0; + j = 0; + let row = 0; + let col = matrix.length - 1; + + // Backwards slash diagonal product comparison, starting at bottom left + for (i; i <= maxIterationsRow; i++) { + for (j; j <= maxIterationsCol; j++) { + currentProduct = + matrix[row][col] * + matrix[row + 1][col - 1] * + matrix[row + 2][col - 2] * + matrix[row + 3][col - 3]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + // if there is space for more multiplications along same diagonal, keep going + if (i <= maxIterationsRow) { + let k = row + 1; + let l = col - 1; + while (k <= maxIterationsRow) { + currentProduct = + matrix[k][l] * + matrix[k + 1][l - 1] * + matrix[k + 2][l - 2] * + matrix[k + 3][l - 3]; + if (currentProduct > biggestProduct) { + biggestProduct = currentProduct; + } + l--; + k++; + } + } + } + } + return biggestProduct; +} // The following is required to make unit tests work. /* Environment setup. Do not modify the below code. */ -if (typeof module !== 'undefined') { +if (typeof module !== "undefined") { module.exports = { maxOfTwoNumbers, findLongestWord, @@ -125,6 +471,6 @@ if (typeof module !== 'undefined') { uniquifyArray, doesWordExist, howManyTimes, - greatestProduct + greatestProduct, }; }