ironhack-174-lab-javascript-functions-and-arrays-partial-solution.js

// Iteration 1
function maxOfTwoNumbers(a, b) {
  if (a > b) return a;
  return b;
}

// Iteration 2
function findLongestWord(arrayOfWords) {
  if (arrayOfWords.length === 0) {
    return null;
  }
  let longestWord;
  for (let word of arrayOfWords) {
    if (typeof longestWord === 'undefined' || word.length > longestWord.length) {
      longestWord = word;
    }
  }
  return longestWord;
}

// Iteration 3
function sumArray(arrayOfNumbers) {
  let sum = 0;
  for (let number of arrayOfNumbers) {
    sum += number;
  }
  return sum;
}

// Iteration 4
function averageNumbers(arrayOfNumbers) {
  if (arrayOfNumbers.length === 0) {
    return null;
  }
  const sum = sumArray(arrayOfNumbers);
  const average = sum / arrayOfNumbers.length;
  return average;
}

// Iteration 5
function averageWordLength(arrayOfWords) {
  if (!arrayOfWords.length) return null;
  const numberOfWords = arrayOfWords.length;
  let totalLength = 0;
  for (let word of arrayOfWords) {
    totalLength += word.length;
  }
  const averageLength = totalLength / numberOfWords;
  return averageLength;
}

// Iteration 6
function uniquifyArray(arrayOfWords) {
  const arrayOfUniques = [];
  for (let word of arrayOfWords) {
    if (arrayOfUniques.indexOf(word) < 0) {
      arrayOfUniques.push(word);
    }
  }
  return arrayOfUniques;
}

// Iteration 7
function doesWordExist(arrayOfWords, word) {
  for (let occurrence of arrayOfWords) {
    if (occurrence === word) return true;
  }
  return false;
}

// Iteration 8
function howManyTimes(arrayOfWords, word) {
  let count = 0;
  for (let occurrence of arrayOfWords) {
    if (occurrence === word) count++;
  }
  return count;
}

// Bonus Iteration

function greatestProduct (matrix) {
  let greatest;

  // CHECK COMBINATIONS HORIZONTALY
  for (let r = 0; r < matrix.length; r++) {
    for (let i = 0; i < matrix[r].length - 4 + 1; i++) {
      const product = matrix[r][i] * matrix[r][i+1] * matrix[r][i + 2] * matrix[r][i + 3];
      if (typeof greatest === 'undefined' || product > greatest) {
        greatest = product;
      }
    }
  }

  // CHECK COMBINATIONS VERTICALY
  for (let c = 0; c < matrix[0].length; c++) {
    for (let i = 0; i < matrix.length - 4 + 1; i++) {
      const product = matrix[i][c] * matrix[i + 1][c] * matrix[i + 2][c] * matrix[i + 3][c];
      if (typeof greatest === 'undefined' || product > greatest) {
        greatest = product;
      }
    }
  }
  
  return greatest;
}