VandyApps Presents:

CODE GOLF

###Objective:

Solve as many coding problems as possible in the given time. The goal is to use as little code as possible to compute your solutions. There are a total of 6 problems that need to be solved. Each problem is scored based upon a combination of correctness and number of characters used.

If you get a problem correct, your score for the problem is: characterCount / problemDifficulty

where characterCount is the amount of characters in your code file (not output file) for the problem being scored

If you get a problem wrong, your score for the problem is: 800 / problemDifficulty

Each problem has a sample input and sample output file to test your code. With 10 minutes left in the competition, the final input files will be published for anyone to see and process. You have 10 minutes to go through the final input files and produce your final output files, which you should submit via email to [email protected].

The final input files will be of the form:

• problem1.final.txt
• problem2.final.txt
• ...problem[#].final.txt

###Submission Instructions

You will be submitting 2 files per problem that you attempt to solve, a file containing the code used to compute the solutions, and a file containing its outputs. Your code will not be executed or interpreted, but will be used to compute your code golf score.

The programming files that you submit must look something like:

• donnyt.4.js
• sandersb.3.php
• [vunetID].[problem #].[extension]

This contains your vunet id, followed by a dot, then the problem number this program is for, followed by another dot, and finally the executable extension. You can program in any language you would like.

Your output files must be in the following format. Note the extension, ''.txt'':

• donnyt.4.txt
• sandersb.1.txt
• [vunetID].[problem #].txt

Submit these files to the [email protected] email with a subject line like "code golf" so that it is clear the solution is meant for code golf.

Please zip or tar your files before submitting them.

###1) Decoding Difficulty level 1

####OVERVIEW

We can represent numbers in a type of character notation with the following rules:

• a indicates add 2
• d indicates decrement
• m indicates multiply by 2
• o indicates output

So, starting with the value 0, the following notation maps to numbers:

• aao -> 4
• aaao -> 6
• aado -> 3
• aamamo -> 20

Note that the o character does not change the value of the number but just indicates that it should be outputted to the screen/file.

So, aaoa will output 4 since o shows up before the last a "add 2".

####PROBLEM: Create a program that converts a file of character notation values into a file of numbers.

The file problem1.practice.txt is sample input for this question and the file problem1s.practice.txt is sample output.

####Clarification

• Each string in character notation will have exactly 1 "o" character. However, that "o" character can appear anywhere in the string.

###2) A Teddy Bear Picnic Difficulty level 2

####OVERVIEW

I decide to give you a lot of teddy bears. You can give me back teddy bears with the following rules:

• If you have an even number of bears, your may give back exactly half of your bears.
• If you have a number of bears that is divisible by 3, then you may multiply the last two digits of this many bears and give me back that many, and one extra bear for good measure. (Note: the last digit of a number n is n%10, and the next-to-last digit is ((n%100)/10).)
• If you have a number of bears divisible by 5, then you may give back exactly 42 bears.
• Otherwise, you can only give back one bear.

The goal is to end up with exactly 42 bears.

For example, if you start with 169 bears:

• Since 169 is not divisible by 2, 3, or 5, you return 1 bear, leaving you with 168 bears.
• Since 168 is divisible by 2, you return 84 bears, leaving you with 84 bears.
• Since 84 is divisible by 2, you return 42 bears, leaving you with 42 bears.
• You have reached the goal!

####PROBLEM

Write a program that, given values for the number of bears given, produces "yes" or "no" on each line depending on if you can end up with 42 bears.

Use the file problem2.practice.txt to test your program. The final test file will have the same format as the practice file.

The file problem2.practice.txt is sample input for this question and the file problem2s.practice.txt is sample output.

###3) Split the Difference Difficulty level 2

####OVERVIEW

A string of numbers contains the numbers 0-9, in strictly increasing order. In between each number, there is a difference. So, for example, the string 025689 has the differences 2, 3, 1, 2, and 1, in order. The goal is to take the string of numbers and split it into two strings, where the sum of the differences is the same in each part. If you receive the string "01268", you should split this string of numbers into the parts "012" and "68" since they both have a sum of differences of 2.

####PROBLEM

You will receive a file containing many strings of numbers, separated by newlines. Your goal is to generate an output file containing the strings broken into substrings, separated by a space. Sample input and output files are given by problem3.practice.txt and problem3s.practice.txt, respectively.

####CLARIFICATION

You can assume all the strings you get as input CAN be broken into 2 strings with equal sums of differences. You can also assume that there is only one possible solution to each string of numbers.

###4) Is it palindrome-able? Difficulty level 2

####OVERVIEW

A palindrome is a word that reads the same backward as forward.

####PROBLEM

Write a program that determines if it is possible to rearrange a given sequence of characters into a palindrome. For example, the string "abcabc" can be rearranged to be "abccba", which is a palindrome, so your program should return "yes". The string "abc" cannot be rearranged into a palindrome, so your program should return "no".

A single character is considered to be a palindrome.

The file problem4.practice.txt is sample input for this question and the file problem4s.practice.txt is sample output.

###5) Encoding Difficulty level 3

####OVERVIEW

This problem is the opposite of problem 1. Take a number and compute a Character Notation version of that number (using a's, d's, m's, and o's). See problem 1 for a description of character notation.

####PROBLEM

You will receive a text file containing a set of numbers separated by newlines. Your job is to generate an output file containing the character notations for those numbers. Keep in mind that there are multiple character notation values that map to the same number (i.e. aamo -> 8 and aaaao -> 8; don't forget to add the o to print out your solution).

You will receive a perfect "correctness" score if all of your number to character count conversions are correct.

The non-whitespace length of your converted solutions will be added to your "Code Golf" score.

The file problem5.practice.txt is sample input for this question and the file problem5s.practice.txt is sample output.

###6) The VandyNacci Sequence Difficulty level 3

####OVERVIEW

In the Fibonacci sequence, each subsequent number in the sequence is the sum of the prior two numbers. In the VandyNacci sequence, each subsequent number in the sequence is the sum of the prior three numbers.

0, 1, 1, 2, 4, 7, 13, 24, 44 ...

####PROBLEM

Write a program that produces the sum of all the VandyNacci numbers that are both divisible by 3 and under a given number. For example, if given the number 30, your program should produce the result 24.

Warning: Your program should be able to handle extremely large numbers. It should also not expect the numbers given to be in increasing order.

The file problem6.practice.txt is sample input for this question and the file problem6s.practice.txt is sample output.