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iOS Closures in Swift 2 Building Standard Library Functions Using Flat Map

Can somebody help me get pass this please?

Using the flatMap function, transform the nested arrays in the numbers constant to a flattened array.

Assign the result to a constant named flattenedNumbers.

flatMap.swift
let numbers = [[1,2,3], [4,5,6], [7,8,9]]

1 Answer

David Papandrew
David Papandrew
8,386 Points
let flattenedNumbers = numbers.flatMap { $0 }