Daily Programming Challenges

Still happily taking coding questions here; this blog is dormant, not inactive. 

My first thought would be to convert to binary, strip 0s and find the length. Like:Integer.toBinaryString(integer).replace("0", "").length();Though, depending on the implementation of ‘replace’, that might not count as without loops. I wouldn’t be surprised if there’s a better trick to find out by looking at bits / distance from power of two or something along those lines, but my search isn’t turning anything good up right now. (Feel free to let me know, though)

The simplest way is just iterating over them to get the sum, and then dividing to find the average. So justdouble sum = 0;for (int i = 0; i < n; i++){    sum += grade[i];}doubleaverage = sum/n;

Good luck you all with your own programming!

So this one is about finding ‘Ruth-Aaron pairs’, which are pairs of consecutive numbers where the prime factors for each sum to the same number. Hopefully it’s clear enough what the code does, but it just goes through each number breaking it down into prime factors using some leftover stuff from the prime factor tree code. 

Due to crushing time constraints, today’s one is just a suuuuuper watered down version of this one; honestly it has little to do with the spreadsheet development thing, but I am super-busy and low on challenges, so! It can take input in the format cell = number, or cell = cell + number, it takes instructions in a set and iterates through them all, remembering set variables for each time. Basically it’s just a little variable-setting program but shhh

Today’s one is about outputting all the cells that would be selected from a spreadsheet range; it takes range : and & and one exclude ~ command per input (and it’s trusting), and it works in Char-Int format (though the actual cells convert the letters to numbers first) annnd it’s ‘part one’ but I don’t think I’ll do the next one (or it’ll be a very cut down version). 

Maybe this one is easier in other languages, but it’s definitely one of the longer easy ones I’ve done. It’s about carry adding - showing addition like when you do it by hand, putting the ones on top - but it is one-hundred percent string alignment which makes it long and tedious and fiddly =P Basically, it just iterates along the rows summing up characters from each line and the carry line, and if the sum is more than one digit it adds it to the carry line. (Plus a whole bunch of string alignment stuff). 

Thiiiis one is kind of like a spell checker; it checks words against dictionary words, finds the point where there are no more matches (where the typo was made) and prints it out with a ‘~’ before the first incorrect character. Then it prints all the words that start with the correct part of the word. Maybe a smarter solution would have been to print anagrams or suggestions only using the inputted letters, but I didn’t feel like digit matching today =B

This one is kind of a little ‘day planner’ thing? It’s not the fullest implementation because I really need to be doing other things, but it can add and delete events, and it does sort them by time, so it achieves the most basic features. You’ve probably seen this kind of code from me before though, pretty simple user input parsing with a scanner. 

This one is a unit calculator - it can convert between a handful of predefined units, by looking at the relative ratios. It’s extensible, so long as you get the proper ratio between the new unit and meters/hogsheads for length or mass. I did pinch the ratios from someone else’s answer on the challenge page to save me the work hehehe

I really don’t understand why this challenge is called ‘vampire numbers’ but I guess I would have just called it ‘numbers that multiply into numbers with the same digits’ so maybe I’m boring. So! It’s numbers that multiply into numbers with the same digits! And it’s not quite an implementation of what the challenge wanted, since it’s strictly two two-digit numbers making a four-digit number, and not flexible lengths, but I am very tired today so this is the best I’m doing =B

This one is probably a pretty lazy implementation by me :V The thing is to take in header text and body text, and use those plus a really basic html format to generate an HTML file. So I did ask-user-with-scanner and wrote out with print writer, and I compressed the HTML template in a really ugly way, and it generates an incredibly plain little page. If you wanted to skip the outputting, a lot of Swing elements can display HTML-encoded text. 

A verrrry long time ago I did part one; today I finally got around to part two of Rock Paper Scissors Lizard Spock! It uses the same base game code (cleaned up) except this time the computer’s choice isn’t random; instead it looks at all the player’s past inputs and picks one of the weaknesses to the one-or-two most common ones. I realised the printed output is a little out of order since the choice the user has just made isn’t included in the calculations, but hopefully all the extra print stuff makes that clear. The program will look for a common weakness between two inputs tied for most common, but if there’s three or more most common it just picks randomly.