Exercises about JavaScript functions

1. CS425 - Web and Mobile Software Engineering
Dr. Lilia Sfaxi
8 février 2017
JavaScript Functions
Exercises
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I. Write a JavaScript function that accepts a string as a parameter and converts the first
letter of each word of the string in upper case.
Example string : 'the quick brown fox'
Expected Output : 'The Quick Brown Fox ‘
II. Write a JavaScript function that accepts a string as a parameter and finds the longest
word within the string.
Example string : 'Web Development Tutorial'
Expected Output : ‘Development'
III. Write a JavaScript function that accepts a string as a parameter and counts the
number of vowels within the string.
Note : As the letter 'y' can be regarded as both a vowel and a consonant, we do not count
'y' as vowel here.
Example string : 'The quick brown fox'
Expected Output : 5
IV. Write a JavaScript function that accepts a number as a parameter and checks if the
number is prime or not.
Note : A prime number (or a prime) is a natural number greater than 1 that has no
positive divisors other than 1 and itself.
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2. V. You are going to be given an array of integers. Your job is to take that array and
find an index N where the sum of the integers to the left of N is equal to the sum of the
integers to the right of N. If there is no index that would make this happen, return -1.
For example:
Let's say you are given the array {1,2,3,4,3,2,1}:
Your function will return the index 3, because at the 3rd position of the array, the sum
of left side of the index ({1,2,3}) and the sum of the right side of the index ({3,2,1}) both
equal 6.
VI. Given a positive integer n written as abcd... (a, b, c, d... being digits) and a positive
integer p we want to find a positive integer k, if it exists, such as the sum of the digits of n
taken to the successive powers of p is equal to k * n. In other words:
Is there an integer k such as : (a ^ p + b ^ (p+1) + c ^(p+2) + d ^ (p+3) + ...) = n * k
If it is the case we will return k, if not return -1.
Note: n, p will always be given as strictly positive integers.
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