solutions.js

// Solutions - Javascript Functions


// return a new string that is the combination of the two parameters
// Example: combineWords('dog', 'house') => 'doghouse'
function combineWords(word1, word2) {
	var result = word1+word2;
	return result;
}
//combineWords("dog", "house");



// display the phrase to the console n times
function repeatPhrase(phrase, n) {
	for(var i = 0; i < n; i++) {
		console.log(phrase);
	}
}
//repeatPhrase ("Hello", 5);



// display number ^ power without using built-in Math functions
function toTheNthPower(number, power) {
	var result = 1;
	for(var i = 0; i < power; i++) {
		result *= number;
	}
	return result;
}
//toTheNthPower(4, 4);



// calculate the area of a circle (pi * r^2)
function areaOfACircle(radius) {
	var r = radius * radius;
	var area = Math.PI * r;
	return area;
}
//areaOfACircle(2);



// Pythagorean Theorem: solve (a^2 + b^2 = c^2) for c
function pythagoreanTheorem(x1, y1, x2, y2) {
	var a = Math.abs(y1 - x1);
	var b = Math.abs(y2 - x2);
	var c = (a * a) + (b * b);
	c = Math.sqrt(c);
	return c;
}
//pythagoreanTheorem(0,3,4,0);


// check if x is evenly divisible by y
function isXEvenlyDivisibleByY(x, y) {
	var result = x % y === 0;
	return result;
}
//isXEvenlyDivisibleByY(98, 3);



// count the number of occurence of vowels in a word.
// vowels are "a", "e", "i", "o", "u", "y"
function countVowels(word) {
	var count = 0;
	word = word.toLowerCase();
	for(var i = 0; i < word.length; i++) {
		if( word[i] === 'a' || word[i] === 'e' || word[i] === 'i' || word[i] === 'o' ||  word[i] === 'u' ||  word[i] === 'y'){
			count++;
		}
	}
	return count;
}
//countVowels("AEIOUY");

// Given an array, return true if it contains the string
// "wdi" and false if it does not contain that string.
function findWdi(arr){
	for (var i = 0; i < arr.length; i++) {
		if(arr[i] === 'wdi'){
			return true;
		}
	}
	return false;
}

// Given a string representing a sentence, return the
// longest word in that sentence.
function findLongestWord(sentence) {
	var longestIndex = 0;
	var arr = sentence.split(" ");
	for (var i = 1; i < arr.length; i++) {
		if (arr[i].length > arr[longestIndex].length) {
			longestIndex = i;
		}
	}
	return arr[longestIndex];
}
// print a simple triangle with asterisks (ASCII Art!!!)
// Example: printTriangle(5)
// Result:
// *
// **
// ***
// ****
// *****
function printTriangle(length) {
	for(var i = 1; i <= length; i++) {

		var tier = '';

		for(var j = 0; j < i; j++) {
			tier += '*';
		}

		console.log(tier);
	}
}
//printTriangle(3);


// Stretch Challenge: Can you alter the printTriangle function to crate a Pyramid?
// Example:
// printPyramid(10)
//           *
//          * *
//         * * *
//        * * * *
//       * * * * *
//      * * * * * *
//     * * * * * * *
//    * * * * * * * *
//   * * * * * * * * *
//  * * * * * * * * * *
// Warning: This is a surprisingly tricky interview-level exercise.
function printPyramid(length) {
	for(var i = 1; i <= length; i++) {
		var tier = '';

		for(var j = length - i; j > 0; j--) {
			tier += ' ';
		}
		for(var k = 0; k < i; k++) {
			tier += '* ';
		}
		console.log(tier);
	}
}
//printPyramid(10);