Ten Simple Javascript Exercises

  1. Define a function max() that takes two numbers as arguments and returns the largest of them. Use the if-then-else construct available in Javascript.

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  2. Define a function maxOfThree() that takes three numbers as arguments and returns the largest of them.

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  3. Write a function that takes a character (i.e. a string of length 1) and returns true if it is a vowel, false otherwise.

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  4. Write a function translate() that will translate a text into "rövarspråket". That is, double every consonant and place an occurrence of "o" in between. For example, translate("this is fun") should return the string "tothohisos isos fofunon".

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  5. Define a function sum() and a function multiply() that sums and multiplies (respectively) all the numbers in an array of numbers. For example, sum([1,2,3,4]) should return 10, and multiply([1,2,3,4]) should return 24.

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  6. Define a function reverse() that computes the reversal of a string. For example, reverse("jag testar") should return the string "ratset gaj".

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  7. Represent a small bilingual lexicon as a Javascript object in the following fashion {"merry":"god", "christmas":"jul", "and":"och", "happy":gott", "new":"nytt", "year":"år"} and use it to translate your Christmas cards from English into Swedish.

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  8. Write a function findLongestWord() that takes an array of words and returns the length of the longest one.

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  9. Write a function filterLongWords() that takes an array of words and an integer i and returns the array of words that are longer than i.

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  10. Write a function charFreq() that takes a string and builds a frequency listing of the characters contained in it. Represent the frequency listing as a Javascript object. Try it with something like charFreq("abbabcbdbabdbdbabababcbcbab").

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