Method with if statement with syntax error

Question

I'm doing some Ruby excercises. My goal is to create a method which reproduces the first and last number of an array.

My way of thinking was:

#create array
a = [1,2,3,4]
#create method
def lastFirst
   return a[0,3]
end
#call the method with an array
lastFirst(a)

But this produces [1,2,3] instead of what I want, which is (1,3).

Any thoughts on what I'm doing wrong?

the Tin Man · Accepted Answer · 2014-12-18 16:20:37Z

5

a[0,3]

　means get 3 elements starting from offset 0.

Try this:

def lastFirst(a)
  [a.first, a.last]
end

the Tin Man

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answered Dec 18, 2014 at 15:59

shirakia

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Comments

the Tin Man · Accepted Answer · 2014-12-18 16:20:21Z

4

Write it using the Array#values_at method:

#create array
a = [1,2,3,4]
#create method
def last_first(a)
  a.values_at(0, -1)
end
#call the method
last_first(a) # => [1, 4]

the Tin Man

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answered Dec 18, 2014 at 15:59

Arup Rakshit

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