Array element additions in ruby -


i have array:

a1 = [1,2,3,4]

i want generate array a1:

a2 = [3, 5, 7]

the formula [a1[0] + a1[1], a1[1] + a1[2], ...].

what ruby way this?

yes, can below:

a1 = [1,2,3,4] a2 = a1.each_cons(2).map{ |a| a.inject(:+) } #=> [3, 5, 7]

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