JavaScript Challenges :turtle:

--- tags:'Short Course' --- # JavaScript Challenges :turtle:  ## No.1: Write a function that can... Return the string "I am a function" :scream: Hint: this function doesn't need to be passed any arguments! Should return something like: `"I am a function"` --- ## No.2: Write a function that can... Take a number as an argument, and return a new value that is 1 less than the argument. :cactus: For example, if I called your function like so `yourFunction(23);` it should return `22` --- ## No.3: Write a function that can... Speak back to you! :wave: Whatever argument you pass to your function, it should simply return that argument back. So `argumentRepeater("Lemon");` should return `"Lemon"` --- ## No.4: Write a function that can... Take **two** numbers as arguments, and return the sum of them :sun_with_face: For example, if you call your function like this: `addTwoNumbers(12, 56);` should return `68` --- ## No.5: Write a function that can... Say who it was written by! :sunglasses: Your function should take a name as an argument, and return the string "This function was written by ____" So `yourFunction("Charlie");` should return `"This function was written by Charlie"` Hint: the "+" key may come in handy... --- ## No.6: Write a function that can... Take 4 numbers as arguments. It should take the sum of the first two arguments, multiply it by the sum of the last two arguments, and return the result :+1: So `yourFunction(2, 3, 6, 4);` should return `50` Hint: using multiple variables inside the statement of your function might make things easier... --- ## No.7: Write a function that can... Take a string as an argument, and return the length (how many characters) of that string. :straight_ruler: So `yourFunction("How long is this string?");` should return `24` Hint: [This freeCodeCamp challenge](https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/find-the-length-of-a-string) may help you if you're stuck, or try reading up in the [MDN docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/length) --- ## No.8: Write a function that can ... Take a number as an argument and returns half that number So `yourFunction(42)` should return `21` and `yourFunction(11)` should return `5.5` --- ## No.9: Write a function that can ... Take two numbers as arguments. If both arguments are equal, return the string `"The first and second arguments are equal"` If the arguments are not equal, return the string `"The first argument ___ does not equal the second argument ___ "`. So `yourFunction(1, 1)` should return `"The first and second arguments are equal"` and `yourFunction(1, 2)` should return `"The first argument 1 does not equal the second argument 2"` Hint: You'll need to use an `if` statement... --- ## No.10: Write a function that can ... Take two numbers as an argument and returns the smallest one. So `yourFunction(11, 2)` should return `2` and `yourFunction(1, -111)` should return `-111` --- ## No.11: Write a function that can ... Take three numbers and returns `true` if the numbers are ascending in size, and false otherwise. So `yourFunction(1, 4, 9)` should return `true` and `yourFunction(4, 1, 10)` should return `false` --- ## No.12: Write a function that can ... Concatenate two strings. So `yourFunction('hi ', 'there')` should return `'hi there'` ## No.13 Write a function that can ... Take an array and a number and return the element of the array at that index. If the number is not a valid index, return `null`. So `yourFunction([7, 3, 5], 2)` should return `5` and `yourFunction([0, 5, 3], 9)` should return `null` Hint: you will need to find the length of the array first, remember zero indexing... ## No.14 Write a function that can ... Take an object, a string, and another value. If the object contains a key that matches the string, return the value corresponding to that key. If the object does not contain a key that matches the string, return the third argument. So `yourFunction({ name: 'felicia', age: 23 }, 'age', 0)` should return `23` and `yourFunction({ name: 'felicia', age: 23 }, 'nickname', 'none')` should return `'none'` ## No.15 Write a function that can ... Take an object whose values are all numbers, and return the sum of those numbers So `yourFunction({ a: 12, b: -4, c: 0.4 })` should return `8.4`

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