Code Golf: Duplicate Character Removal in String

Posted by Alex on Stack Overflow See other posts from Stack Overflow or by Alex
Published on 2009-08-27T23:57:50Z Indexed on 2011/01/10 12:53 UTC
Read the original article Hit count: 217

Filed under:

code-golf

The challenge: The shortest code, by character count, that detects and removes duplicate characters in a String. Removal includes ALL instances of the duplicated character (so if you find 3 n's, all three have to go), and original character order needs to be preserved.

Example Input 1:
nbHHkRvrXbvkn

Example Output 1:
RrX

Example Input 2:
nbHHkRbvnrXbvkn

Example Output 2:
RrX

(the second example removes letters that occur three times; some solutions have failed to account for this)

(This is based on my other question where I needed the fastest way to do this in C#, but I think it makes good Code Golf across languages.)

Related posts about code-golf

Code Golf: Collatz Conjecture

as seen on Stack Overflow - Search for 'Stack Overflow'
Inspired by http://xkcd.com/710/ here is a code golf for it. The Challenge Given a positive integer greater than 0, print out the hailstone sequence for that number. The Hailstone Sequence See Wikipedia for more detail.. If the number is even, divide it by two. If the number is odd, triple… >>> More
Code Golf - p day

as seen on Stack Overflow - Search for 'Stack Overflow'
The Challenge The shortest code by character count to display a representation of a circle of radius R using the *character, followed by an approximation of p. Input is a single number, R. Since most computers seem to have almost 2:1 ratio you should only output lines where y is odd. The approximation… >>> More
Code Golf - PI day

as seen on Stack Overflow - Search for 'Stack Overflow'
The Challenge The shortest code by character count to display a representation of a circle of radius R using the *character. Followed by an approximation of pi Input is a single number, R Since most computers seem to have almost 2:1 ratio you should only output lines where y is odd. The approximation… >>> More
Code Golf: Triforce

as seen on Stack Overflow - Search for 'Stack Overflow'
This is inspired by/taken from this thread: http://www.allegro.cc/forums/thread/603383 The Problem Assume the user gives you a numeric input ranging from 1 to 7. Input should be taken from the console, arguments are less desirable. When the input is 1, print the following: *********** *********… >>> More
Code Golf: Tic Tac Toe

as seen on Stack Overflow - Search for 'Stack Overflow'
Post your shortest code, by character count, to check if a player has won, and if so, which. Assume you have an integer array in a variable b (board), which holds the Tic Tac Toe board, and the moves of the players where: 0 = nothing set 1 = player 1 (X) 2 = player 2 (O) So, given the array b… >>> More

Developer IT