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iOS Closures in Swift 2 Building Standard Library Functions Using Reduce

Posted by Chris Smith
Chris Smith
6,791 Points

I'm stuck on the Reduce Function Swift task. Please help!

Q: In the editor you've been provided with an array of several people's ages. Using the reduce function, calculate the sum of the ages and assign it to a value named total.

I thought that I understood Reduce Functions... Can someone please tell me where I am going wrong? Thanks in advance.

reduce.swift 
let ages = [12,10,11,42,35,27,91,82,26,33,37,15]
let total = ages.reduce(0, {total, age in total + age})
Jeff Ripke
Jeff Ripke
41,989 Points
Jeff Ripke
Jeff Ripke
41,989 Points

They want it in a simpler form:

let ages = [12,10,11,42,35,27,91,82,26,33,37,15]
let total = ages.reduce(0, combine: +)

I hope this helps, Jeff

Chris Smith
Chris Smith
6,791 Points

Hi Jeff Ripke, thank you. I actually managed to figure it out in the end. :)

1 Answer

John Hendrix
John Hendrix
21,844 Points
John Hendrix
John Hendrix
21,844 Points

Hi Jeff Ripke , I received an error that stated combine: needed to be changed to _:

The below code worked for me.

let ages = [12,10,11,42,35,27,91,82,26,33,37,15]

let total = ages.reduce(0, _: +)