First JS

Find Max Number

Write a function called findMaxNumber that takes in an array of numbers and returns the largest number in the array.

Solution 1

function findMaxNumber(arr) {
  return Math.max(...arr);
}

Solution 2

function findMaxNumber(arr) {
  let max = arr[0];

  for (let i = 1; i < arr.length; i++) {
    if (arr[i] > max) {
      max = arr[i];
    }
  }
  return max;
}

findMaxNumber([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]); // 10
findMaxNumber([10, 9, 8, 7, 6, 5, 4, 3, 2, 1]); // 10
findMaxNumber([1, 2, 3, 4, 5, 10, 9, 8, 7, 6]); // 10

Solution 3

  function findMaxNumber(arr) {
    if (arr.length === 0) {
        return undefined; // return undefined for an empty array
    }

    let max = arr[0]; // Assume the first element is the maximum

    for (let i = 1; i < arr.length; i++) {
        if (arr[i] > max) {
            max = arr[i]; // Update max if current element is greater
        }
    }

    return max; // Return the maximum number
}

// Example usage:
const numbers = [10, 5, 20, 8, 15];
console.log(findMaxNumber(numbers)); // Output: 20

Uisng a switch:

function calculator(num1, num2, operator) {
  let result;

  switch (operator) {
    case '+':
      result = num1 + num2;
      break;
    case '-':
      result = num1 - num2;
      break;
    case '*':
      result = num1 * num2;
      break;
    case '/':
      result = num1 / num2;
      break;
    default:
      throw new Error('Invalid operator');
  }

  return result;
}

calculator(1, 2, '+') // 3
calculator(10, 5, '-') // 5
calculator(2, 2, '*') // 4
calculator(10, 5, '/') // 2

Using an if statement:

function calculator(num1, num2, operator) {
  let result;

  if (operator === '+') {
    result = num1 + num2;
  } else if (operator === '-') {
    result = num1 - num2;
  } else if (operator === '*') {
    result = num1 * num2;
  } else if (operator === '/') {
    result = num1 / num2;
  } else {
    throw new Error('Invalid operator');
  }

  return result;
}

function getSum(a, b) {
  return a + b;
}

function printHelloWorld() {
  return 'Hello World!';
}