Exercises on the TypeScript Track | Exercism

Hello World

The classical introductory exercise. Just say "Hello, World!"

control flow conditionals

optional values

text formatting

Two Fer

Create a sentence of the form "One for X, one for me."

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Leap

Given a year, report if it is a leap year.

Simple Cipher

Implement a simple shift cipher like Caesar and a more secure substitution cipher

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text formatting

Armstrong Numbers

Determine if a number is an Armstrong number

Run Length Encoding

Implement run-length encoding and decoding.

control flow conditionals

exception handling

pattern recognition

regular expressions

text formatting

Reverse String

Reverse a string

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

Bob

Bob is a lackadaisical teenager. In conversation, his responses are very limited.

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pattern recognition

regular expressions

Protein Translation

Translate RNA sequences into proteins.

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control flow loops

Pangram

Determine if a sentence is a pangram.

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Isogram

Determine if a word or phrase is an isogram.

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Space Age

Given an age in seconds, calculate how old someone is in terms of a given planet's solar years.

floating point numbers

Perfect Numbers

Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60 - 120 CE) classification scheme for natural numbers.

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Roman Numerals

Write a function to convert from normal numbers to Roman Numerals.

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pattern recognition

Diffie Hellman

Diffie-Hellman key exchange.

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exception handling

Strain

Implement the `keep` and `discard` operation on collections. Given a collection and a predicate on the collection's elements, `keep` returns a new collection containing those elements where the predicate is true, while `discard` returns a new collection containing those elements where the predicate is false.

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Twelve Days

Output the lyrics to 'The Twelve Days of Christmas'

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pattern recognition

Prime Factors

Compute the prime factors of a given natural number.

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Matrix

Given a string representing a matrix of numbers, return the rows and columns of that matrix.

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data structures

text formatting

Saddle Points

Detect saddle points in a matrix.

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Nucleotide Count

Given a DNA string, compute how many times each nucleotide occurs in the string.

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text formatting

Pig Latin

Implement a program that translates from English to Pig Latin

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regular expressions

Luhn

Given a number determine whether or not it is valid per the Luhn formula.

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Transpose

Take input text and output it transposed.

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control flow loops

text formatting

ISBN Verifier

Check if a given string is a valid ISBN-10 number.

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pattern recognition

regular expressions

Proverb

For want of a horseshoe nail, a kingdom was lost, or so the saying goes. Output the full text of this proverbial rhyme.

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optional values

text formatting

Complex Numbers

Implement complex numbers.

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House

Output the nursery rhyme 'This is the House that Jack Built'.

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Rectangles

Count the rectangles in an ASCII diagram.

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Spiral Matrix

Given the size, return a square matrix of numbers in spiral order.

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data structures

Nth Prime

Given a number n, determine what the nth prime is.

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exception handling

Sum Of Multiples

Given a number, find the sum of all the multiples of particular numbers up to but not including that number.

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control flow loops

Linked List

Implement a doubly linked list

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control flow loops

data structures

optional values

Bracket Push

Make sure the brackets and braces all match.

Flatten Array

Take a nested list and return a single list with all values except nil/null

Grains

Calculate the number of grains of wheat on a chessboard given that the number on each square doubles.

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Sieve

Use the Sieve of Eratosthenes to find all the primes from 2 up to a given number.

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Sublist

Write a function to determine if a list is a sublist of another list.

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data structures

Accumulate

Implement the `accumulate` operation, which, given a collection and an operation to perform on each element of the collection, returns a new collection containing the result of applying that operation to each element of the input collection.

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All Your Base

Convert a number, represented as a sequence of digits in one base, to any other base.

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exception handling

Secret Handshake

Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.

bitwise operations

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Allergies

Given a person's allergy score, determine whether or not they're allergic to a given item, and their full list of allergies.

bitwise operations

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control flow loops

Binary Search Tree

Insert and search for numbers in a binary tree.

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control flow loops

Robot Name

Manage robot factory settings.

control flow conditionals

exception handling

regular expressions

Grade School

Given students' names along with the grade that they are in, create a roster for the school

Custom Set

Create a custom set type.

control flow conditionals

control flow loops

data structures

Wordy

Parse and evaluate simple math word problems returning the answer as an integer.

control flow conditionals

control flow loops

exception handling

pattern recognition

regular expressions

Minesweeper

Add the numbers to a minesweeper board

Connect

Compute the result for a game of Hex / Polygon

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Palindrome Products

Detect palindrome products in a given range.

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Circular Buffer

A data structure that uses a single, fixed-size buffer as if it were connected end-to-end.

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control flow loops

data structures

exception handling

List Ops

Implement basic list operations

data structures

Bowling

Score a bowling game

control flow conditionals

control flow loops

exception handling

text formatting

Queen Attack

Given the position of two queens on a chess board, indicate whether or not they are positioned so that they can attack each other.

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exception handling

optional values

text formatting

Crypto Square

Implement the classic method for composing secret messages called a square code.

control flow conditionals

control flow loops

regular expressions

text formatting

Gigasecond

Given a moment, determine the moment that would be after a gigasecond has passed.

Series

Given a string of digits, output all the contiguous substrings of length `n` in that string.

control flow loops

exception handling

text formatting

Difference Of Squares

Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.

control flow loops

Word Count

Given a phrase, count the occurrences of each word in that phrase.

control flow loops

regular expressions

Raindrops

Convert a number to a string, the contents of which depend on the number's factors.

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ETL

We are going to do the `Transform` step of an Extract-Transform-Load.

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Hamming

Calculate the Hamming difference between two DNA strands.

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control flow loops

Scrabble Score

Given a word, compute the scrabble score for that word.

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control flow loops

Acronym

Convert a long phrase to its acronym

control flow loops

regular expressions

Anagram

Given a word and a list of possible anagrams, select the correct sublist.

Phone Number

Clean up user-entered phone numbers so that they can be sent SMS messages.

Beer Song

Produce the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.

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Say

Given a number from 0 to 999,999,999,999, spell out that number in English.

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control flow loops

exception handling

text formatting

Food Chain

Generate the lyrics of the song 'I Know an Old Lady Who Swallowed a Fly'

text formatting

Clock

Implement a clock that handles times without dates.

Triangle

Determine if a triangle is equilateral, isosceles, or scalene.

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control flow loops

exception handling

Collatz Conjecture

Calculate the number of steps to reach 1 using the Collatz conjecture

exception handling

Pascal's Triangle

Compute Pascal's triangle up to a given number of rows.

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control flow loops

Rational Numbers

Implement rational numbers.

floating point numbers

Binary Search

Implement a binary search algorithm.

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control flow loops

Rotational Cipher

Create an implementation of the rotational cipher, also sometimes called the Caesar cipher.

Largest Series Product

Given a string of digits, calculate the largest product for a contiguous substring of digits of length n.

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exception handling

regular expressions

Kindergarten Garden

Given a diagram, determine which plants each child in the kindergarten class is responsible for.

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text formatting

Robot Simulator

Write a robot simulator.

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exception handling

Pythagorean Triplet

There exists exactly one Pythagorean triplet for which a + b + c = 1000. Find the product a * b * c.

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OCR Numbers

Given a 3 x 4 grid of pipes, underscores, and spaces, determine which number is represented, or whether it is garbled.

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control flow loops

exception handling

text formatting

Diamond

Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.

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exception handling

text formatting

Two Bucket

Given two buckets of different size, demonstrate how to measure an exact number of liters.

control flow conditionals

control flow loops

exception handling

Variable Length Quantity

Implement variable length quantity encoding and decoding.

bitwise operations

control flow conditionals

control flow loops

exception handling

Atbash Cipher

Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.

control flow conditionals

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text formatting

Alphametics

Write a function to solve alphametics puzzles.