Exercise 1: Reverse a String
Write a function that reverses a string. Try multiple approaches: using split/reverse/join, or a loop.
function reverseString(str) {
return str.split("").reverse().join("");
}
console.log(reverseString("hello"));
console.log(reverseString("JavaScript"));
console.log(reverseString("racecar"));Exercise 2: Find Maximum
Find the largest number in an array. Try implementing it with a loop and with Math.max.
function findMax(arr) {
if (arr.length === 0) return null;
let max = arr[0];
for (let i = 1; i < arr.length; i++) {
if (arr[i] > max) {
max = arr[i];
}
}
return max;
}
function findMaxSimple(arr) {
return arr.length ? Math.max(...arr) : null;
}
console.log(findMax([3, 7, 2, 9, 5]));
console.log(findMaxSimple([-10, -3, -25, -1]));Exercise 3: FizzBuzz
Print numbers 1 to n: multiples of 3 print "Fizz", multiples of 5 print "Buzz", multiples of both print "FizzBuzz".
function fizzbuzz(n) {
const result = [];
for (let i = 1; i <= n; i++) {
if (i % 15 === 0) result.push("FizzBuzz");
else if (i % 3 === 0) result.push("Fizz");
else if (i % 5 === 0) result.push("Buzz");
else result.push(i);
}
return result;
}
console.log(fizzbuzz(15).join(", "));