The Ruby Programming Blog

facebook careers puzzle – Hoppity Hop! – in Ruby

rishabh — Tue, 20 Sep 2011 17:54:23 +0000

https://www.facebook.com/careers/puzzles.php?puzzle_id=7

A pretty simple puzzle just to get things started. Hoppity Hop!

def hoppity_hop
	#fetch the file name from the command prompt input
	file_name = ARGV[0]
	#read the contents from the file and convert to integer
	file_content = File.read(file_name).to_i
 
	#run loop from 1 to the number in file
	1.upto(file_content) do |i|
		if i % 3 == 0 &amp;&amp; i % 5 == 0
			puts "Hop\n"
		else
			puts "Hoppity\n" if i % 3 == 0
			puts "Hophop\n" if i % 5 == 0
		end
 
	end
end
 
hoppity_hop

Binary Search – Ruby Programming Language

rishabh — Mon, 15 Aug 2011 17:56:20 +0000

Binary Search, takes in sorted array and search the key element and returns the index of the key element.

View Code RUBY

def binarySearch(sortedArray, first, last, key) 
   until first > last do
       mid = (first + last)/2
       if (key > sortedArray[mid])
           first = mid + 1;
           binarySearch(sortedArray, first, last, key)
       elsif (key < sortedArray[mid])
           last = mid - 1;
           binarySearch(sortedArray, first, last, key)
       else
           return mid;
      end
   end
   return -1;
end
 
sorted_array = [1, 5, 6, 18, 19, 25, 46, 78, 102, 114]
p binarySearch(sorted_array, 0, sorted_array.length-1, 6)

Another attempt, optimized binary search without while or any loop. There is no loop. Let me know your view point on this

View Code RUBY

def binarySearch(sortedArray, first, last, key) 
   if first < last
       mid = (first + last)/2
       if (key == sortedArray[mid])
          return mid
       else
         if(key > sortedArray[mid])
           first = mid + 1
         else
           last = mid - 1
         end
       end
       return binarySearch(sortedArray, first, last, key)
   end
   return -1;
end
 
sorted_array = [1, 5, 6, 18, 19, 25, 46, 78, 102, 114]
p binarySearch(sorted_array, 0, sorted_array.length-1, 50)

Astrix (*) Patterns in Ruby

rishabh — Mon, 15 Aug 2011 10:21:15 +0000

This simple program shows the astrix in diamond structure. It takes input from the user and displays a diamond structure astrix. This program is made using Ruby Language. I used Ruby 1.8.7 but it should work on all Ruby versions.

View Code RUBY

def patterns n
	1.upto(n) do |i|
		space = ''
		astrix = ''
		i.upto(n-1) { space=space+' '; }
		1.upto(i) { astrix=astrix+'*'; }
		2.upto(i) { astrix=astrix+'*'; }
		puts space+astrix
	end
	i= n-1
	until i < 1 do
		space = ''
		astrix = ''
		i.upto(n-1) { space=space+' '; }
		1.upto(i) { astrix=astrix+'*'; }
		2.upto(i) { astrix=astrix+'*'; }
		puts space+astrix
		i=i-1
	end
end
 
puts "Enter Number of Iterations"
a = gets.chomp.to_i
 
patterns a

Output: