Find PI to the Nth Digit - Enter a number and have the program generate PI up to that many decimal places. Keep a limit to how far the program will go.
Mortgage Calculator - Calculate the monthly payments of a fixed term mortgage over given Nth terms at a given interest rate. Also figure out how long it will take the user to pay back the loan. For added complexity, add an option for users to select the compounding interval (Monthly, Weekly, Daily, Continually).
Change Return Program - The user enters a cost and then the amount of money given. The program will figure out the change and the number of quarters, dimes, nickels, pennies needed for the change.
Calculator - A simple calculator to do basic operators. Make it a scientific calculator for added complexity.
Unit Converter (temp, currency, volume, mass and more) - Converts various units between one another. The user enters the type of unit being entered, the type of unit they want to convert to and then the value. The program will then make the conversion.
Tax Calculator - Asks the user to enter a cost and either a country or state tax. It then returns the tax plus the total cost with tax.
Coin Flip Simulation - Write some code that simulates flipping a single coin however many times the user decides. The code should record the outcomes and count the number of tails and heads.
Sorting - Implement two types of sorting algorithms: Merge sort and bubble sort.
Fizz Buzz - Write a program that prints the numbers from 1 to 100. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”.
Reverse a String - Enter a string and the program will reverse it and print it out.
Pig Latin - Pig Latin is a game of alterations played on the English language game. To create the Pig Latin form of an English word the initial consonant sound is transposed to the end of the word and an ay is affixed (Ex.: "banana" would yield anana-bay). Read Wikipedia for more information on rules.
Count Vowels - Enter a string and the program counts the number of vowels in the text. For added complexity have it report a sum of each vowel found.
Check if Palindrome - Checks if the string entered by the user is a palindrome. That is that it reads the same forwards as backwards like “racecar”
Count Words in a String - Counts the number of individual words in a string. For added complexity read these strings in from a text file and generate a summary.
RSS Feed Creator - Given a link to RSS/Atom Feed, get all posts and display them.
Bandwidth Monitor - A small utility program that tracks how much data you have uploaded and downloaded from the net during the course of your current online session. See if you can find out what periods of the day you use more and less and generate a report or graph that shows it.
Port Scanner - Enter an IP address and a port range where the program will then attempt to find open ports on the given computer by connecting to each of them. On any successful connections mark the port as open.
Bank Account Manager - Create a class called Account which will be an abstract class for three other classes called CheckingAccount, SavingsAccount and BusinessAccount. Manage credits and debits from these accounts through an ATM style program.
Page Scraper - Create an application which connects to a site and pulls out all links, or images, and saves them to a list. Optional: Organize the indexed content and don’t allow duplicates. Have it put the results into an easily searchable index file.
Fetch Current Weather - Get the current weather for a given zip/postal code. Optional: Try locating the user automatically.
Caesar cipher - Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to "JK", but key 20 encrypts "HI" to "BC". This simple "monoalphabetic substitution cipher" provides almost no security, because an attacker who has the encoded message can either use frequency analysis to guess the key, or just try all 25 keys.
Magic 8 Ball
Pythagorean Triples Checker
Mad Libs Story Maker
Mean, Median, and Mode
Higher Lower Guessing Game
Multiplication Table
Hangman Game
Dice Rolling Simulator
Factors of a Number
Countdown Clock
A Variation of 21
Watch for new TIL facts
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