Backtracking solution in ruby

def exact_sum?(sum, arr)
return true if sum==0
return false if sum < 0 || arr.empty?
# now we are checking both cases
exact_sum?(sum - arr[0], arr[1,arr.length]) || exact_sum?(sum, arr[1,arr.length])
end

puts exact_sum?(12, [1, 2, 3, 4, 5]);
# => true

Source: hackernoon.com

Similar codes

0 vote237 views1 answer
Rails generate model polymorphic references
Ruby
0 vote250 views1 answer
How to push different branch to heroku
Ruby
0 vote240 views1 answer
Rails g model references
Ruby
0 vote234 views1 answer
Next rails gem
Ruby
0 vote250 views1 answer
Difference between is_a and kind_of ruby
Ruby
-1 vote305 views2 answers
Get single hash key ruby
Ruby
8 votes475 views3 answers
Ruby each with index
Ruby
0 vote222 views1 answer
Encryption and decryption in rails
Ruby
0 vote238 views1 answer
Ruby try catch variable and assign nil value
Ruby
1 vote245 views1 answer
Ruby replace certain character
Ruby