CODEWITHSUNDEEP
rubyarraysconcatenation
KevDog
KevDog

Reputation: 5803

How to Concatenate Integer Array to Single Integer in Ruby

Given the array [1,2,3], is there a method (other than just iteration) to convert it to the integer 123?

Upvotes: 10

Views: 8785

Answers (3)

Michael Kohl
Michael Kohl

Reputation: 66837

Personally I would use 

Integer([1,2,3].join, 10) #=> 123

since it has the nice side-effect of throwing an exception that you can deal with if you have non-numeric array elements:

>> Integer([1,2,'a'].join, 10) # ArgumentError: invalid value for Integer: "12a"

Compare this to to_i:

>> [1,2,'a'].join.to_i #=> 12

Upvotes: 7

Mladen Jablanović
Mladen Jablanović

Reputation: 44080

If you want to avoid converting to and from a String, you can use inject:

[1,2,3].inject{|a,i| a*10 + i}
#=> 123

Upvotes: 14

arnep
arnep

Reputation: 6241

Just join the array and convert the resulted string to an integer:

[1,2,3].join.to_i

Upvotes: 19

Related Questions