Web Developer / Blog

Dustin Diaz posted a programming brain teaser on his blog. I decided to take a shot at it and came up with this. The solution took me just under 20 minutes.

Output:

abccdeeeeefefefaaafff

Code:

var arr = ["a", "b", "c", "c", "d","e", "e", "e", "e",
"e", "f", "e", "f", "e", "f", "a", "a", "a", "f", "f", "f"];

var out = ""; // output string
var i; // counter
var prev1 = "-1"; // random unique
var prev2 = "-2"; // random unique
var dups = 0; // duplicate counter
var pdups = 0; // previous duplicate counter value

for(i=0; i= 2 && thisChar != prev1){ // if not matching and exiting span
    out += "";
  }

  out += thisChar; // append this char to output string

  if(i == (arr.length-1) && dups > 0){ // close as needed at end of string
    out += "";
  }

  // prepare for next iteration
  prev2 = prev1;
  prev1 = thisChar;
  pdups = dups;
}

Some interesting solutions from the comments on Dustin’s blog.

• http://dmitry.baranovskiy.com/post/41419429
• http://www.mattryall.net/blog/2008/07/dustins-programming-problem
• http://remysharp.com/downloads/brain-teaser-solution.js

This entry was posted on Monday, July 7th, 2008 at 11:40 pm. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.