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 vote172 views1 answer
If rails.env.development
Ruby
3 votes213 views1 answer
Integer to string ruby
Ruby
13 votes328 views2 answers
Rails validate uniqueness
Ruby
0 vote183 views1 answer
Check ruby version in windows
Ruby
0 vote173 views1 answer
Rails assets video not found video_tag
Ruby
1 vote199 views2 answers
Params except rails
Ruby
0 vote200 views1 answer
How to upload a file in capybara spec
Ruby
0 vote175 views1 answer
Rails optional reference
Ruby
1 vote184 views1 answer
Ruby version from script
Ruby
0 vote187 views1 answer
Preview mailers rails
Ruby