fbslee · August 24, 2016 04:37
diff --git a/checkpointFelipe.js b/checkpointFelipe.js
 # W2D2 Checkpoint

 Submit a link to your gist [here](https://goo.gl/forms/HywFjkNIU9mLM7c03)

 1. Write a function `average` that takes two numbers as input (parameters), and
   returns the average of those numbers.

 function average(num1,num2){
  return (num1 + num2) / 2;
 }

 2. Write a function `greeter` that takes a name as an argument and *greets*
    that name by returning something along the lines of `"Hello, <name>!"`

 function greeter(name){
  return "Hello, " + name + "! How are you?";
 }

 3. Write the following functions that each accept a single number as an
   argument:

    + `even`: returns `true` if its argument is even, and `false` otherwise.
    + `odd`: the opposite of the above.
    + `positive`: returns `true` if its argument is positive, and `false` otherwise.
    + `negative`: the opposite of the above.

 function even(num1){
  return num1 % 2 === 0;
 }
 function odd (num2){
  return num2 % 2 !== 0;
 }
 function positive(num3){
  return num3 > 0;
 }
 function negative(num4){
  return num4 < 0;
 }

 4. Write a function `sayHello` that takes a *language* parameter, and returns
   "hello" in that language. Make the function work with **at least three
   languages**.

 function sayHello(language){
  if(language === "English"){
    return "Hello!";
  }
  if(language === "Portuguese"){
    return "Ola!";
  }
  if(language === "Spanish"){
    return "Hola!";
  }
  return "Unknown language";
 }

 5. Write a function `validCredentials` that accepts two parameters: *username*
   and *password*, and returns `true` if **both** are long enough, and `false`
   otherwise. You can decide what constitutes "long enough".

 function validCredentials(username,password){
  return (username.length >= 6 && password.length >= 6);
 }

 6. **Repeating a String `n` Times:** Let's write a function called
   `repeatString` that takes two parameters: a string `str`, which is the string
   to be repeated, and `count` -- a number representing how many times the
   string `str` should be repeated, *e.g.*

 function repeatString(str,count){
  return str.repeat(count);
 }

   ```js
   function repeatString(str, count) {
     // TODO: your code here
   }
   repeatString('dog', 0); // => ''
   repeatString('dog', 1); // => 'dog'
   repeatString('dog', 2); // => 'dog' + 'dog' => 'dogdog'
   repeatString('dog', 3); // => 'dog' + 'dog' + 'dog' => 'dogdogdog'
   ```

 7. Write a function called `average` that takes an array of numbers as a
   parameter and returns the *average* of those numbers.

 var numbers = [];
 function average(numbers){
  var total = 0;
  for (var i = 0; i < numbers.length; i++){
  total = total + numbers[i]
 }
 return total / numbers.length;
 }

 8. Write a function `countWords` that, when given a string as an argument,
   returns an *object* where *keys* are the words in the string, and *values*
   are the number of occurrences of that word within the string:

   ```js
   function countWords(s) {
   // ...
   }
   countWords("hello hello"); // => {"hello": 2}
   countWords("Hello hello"); // => {"Hello": 1, "hello": 1}
   countWords("The quick brown"); // => {"The": 1, "quick": 1, "brown": 1}
   ```

   **HINT:** You will want to make use of the string method `split`. Try
   `\"Hello hello".split(" ")` at a console to see how it works.

   - Modify `countWords` to be *case insensitive* by using the following string
     method (experiment at a console with it to learn its behavior):

   ```js
   "HElLo".toLowerCase(); // => ???
   ```
 function countWords(s){
  var words = (s.toLowerCase()).split(" ");
  var history = {};
  for (var i = 0; i < words.length; i++){
    if(history[words[i]]){
      history[words[i]]++;
    }
    else {
      history[words[i]] = 1;
    }
  }
  return history;
 }

   
 ### Bonus

 1. Read about the join method on MDN and use it to implement a function that accepts a string
   as an argument and returns that string reversed.

   function reverseString(str){
    return str.split('').reverse().join('');
   }

 2. The function `Object.keys` returns an array of an object's *keys*. Experiment
   with it at the console like this:

   ```js
   Object.keys({a: 1, b: 2});
   ```

   Using this property, write versions of the above functions using repetition
   through function invocation (*i.e.* recursion)
	# W2D2 Checkpoint

	Submit a link to your gist [here](https://goo.gl/forms/HywFjkNIU9mLM7c03)

	1. Write a function `average` that takes two numbers as input (parameters), and
	returns the average of those numbers.

	function average(num1,num2){
	return (num1 + num2) / 2;
	}

	2. Write a function `greeter` that takes a name as an argument and greets
	that name by returning something along the lines of `"Hello, <name>!"`

	function greeter(name){
	return "Hello, " + name + "! How are you?";
	}

	3. Write the following functions that each accept a single number as an
	argument:

	+ `even`: returns `true` if its argument is even, and `false` otherwise.
	+ `odd`: the opposite of the above.
	+ `positive`: returns `true` if its argument is positive, and `false` otherwise.
	+ `negative`: the opposite of the above.

	function even(num1){
	return num1 % 2 === 0;
	}
	function odd (num2){
	return num2 % 2 !== 0;
	}
	function positive(num3){
	return num3 > 0;
	}
	function negative(num4){
	return num4 < 0;
	}

	4. Write a function `sayHello` that takes a language parameter, and returns
	"hello" in that language. Make the function work with **at least three
	languages**.

	function sayHello(language){
	if(language === "English"){
	return "Hello!";
	}
	if(language === "Portuguese"){
	return "Ola!";
	}
	if(language === "Spanish"){
	return "Hola!";
	}
	return "Unknown language";
	}

	5. Write a function `validCredentials` that accepts two parameters: username
	and password, and returns `true` if both are long enough, and `false`
	otherwise. You can decide what constitutes "long enough".

	function validCredentials(username,password){
	return (username.length >= 6 && password.length >= 6);
	}

	6. Repeating a String `n` Times: Let's write a function called
	`repeatString` that takes two parameters: a string `str`, which is the string
	to be repeated, and `count` -- a number representing how many times the
	string `str` should be repeated, e.g.

	function repeatString(str,count){
	return str.repeat(count);
	}

	```js
	function repeatString(str, count) {
	// TODO: your code here
	}
	repeatString('dog', 0); // => ''
	repeatString('dog', 1); // => 'dog'
	repeatString('dog', 2); // => 'dog' + 'dog' => 'dogdog'
	repeatString('dog', 3); // => 'dog' + 'dog' + 'dog' => 'dogdogdog'
	```

	7. Write a function called `average` that takes an array of numbers as a
	parameter and returns the average of those numbers.

	var numbers = [];
	function average(numbers){
	var total = 0;
	for (var i = 0; i < numbers.length; i++){
	total = total + numbers[i]
	}
	return total / numbers.length;
	}

	8. Write a function `countWords` that, when given a string as an argument,
	returns an object where keys are the words in the string, and values
	are the number of occurrences of that word within the string:

	```js
	function countWords(s) {
	// ...
	}
	countWords("hello hello"); // => {"hello": 2}
	countWords("Hello hello"); // => {"Hello": 1, "hello": 1}
	countWords("The quick brown"); // => {"The": 1, "quick": 1, "brown": 1}
	```

	HINT: You will want to make use of the string method `split`. Try
	`\"Hello hello".split(" ")` at a console to see how it works.

	- Modify `countWords` to be case insensitive by using the following string
	method (experiment at a console with it to learn its behavior):

	```js
	"HElLo".toLowerCase(); // => ???
	```
	function countWords(s){
	var words = (s.toLowerCase()).split(" ");
	var history = {};
	for (var i = 0; i < words.length; i++){
	if(history[words[i]]){
	history[words[i]]++;
	}
	else {
	history[words[i]] = 1;
	}
	}
	return history;
	}


	### Bonus

	1. Read about the join method on MDN and use it to implement a function that accepts a string
	as an argument and returns that string reversed.

	function reverseString(str){
	return str.split('').reverse().join('');
	}

	2. The function `Object.keys` returns an array of an object's keys. Experiment
	with it at the console like this:

	```js
	Object.keys({a: 1, b: 2});
	```

	Using this property, write versions of the above functions using repetition
	through function invocation (i.e. recursion)