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50 Swift Interview Questions and Answers
Ace your iOS developer job interview by knowing the answers to these essential questions
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Here’s a list of 50 Swift interview questions and answers. These questions focus on Swift programming and iOS app development. You need to know the answers to these before you get a chance to show your skills in front of a job interviewer.
These questions are in no particular order — let’s get right into it!
1. What Causes an Error? How Can You Fix It?
let n1: Int = 1
let n2: Float = 2.0
let n3: Double = 3.34var result = n1 + n2 + n3
Answer:
In Swift, implicit type casting between two data types is not possible.
In the code above, you’re trying to add three elements together, each of which represents a different data type.
To fix this, you need to convert each value to the same data type. For example:
var result = Double(n1) + Double(n2) + n3
2. What is the Value of Len
? Why?
var arr1 = [1, 2, 3]
var arr2 = arr1arr2.append(4)var len = arr1.count