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iOS Swift Basics (retired) Control Flow While and Do-While Loop

Posted by joshuawalliy
joshuawalliy
1,131 Points

Better understanding

I am not sure what to do. I really don't understand why this is important and how to do it. Could someone help or clarify it better?

while_loops.swift 
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
while numbers is true

2 Answers

Richard Lu
Richard Lu
20,185 Points
Richard Lu
Richard Lu
20,185 Points

Hi Joshua,

The challenge is to print out each number in the given array. In order to do that, you'll need a counter variable. Here's a demonstration of how I solved this problem.

let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

var counter = 0   // the counter variable
while counter < numbers.count {  // while number is less than the length of the array enter this loop
  println(numbers[counter])
  // in this case the last loops counter will be 11 (greater than the length of the array) and will not be able to enter the loop again
  counter = counter + 1   // increase the counter by 1
}

Good luck!

joshuawalliy
joshuawalliy
1,131 Points
joshuawalliy
joshuawalliy
1,131 Points

Thank you. How can this be used for making apps?

Richard Lu
Richard Lu
20,185 Points
Richard Lu
Richard Lu
20,185 Points

Hey Joshua,

This is a tiny part of the puzzle of building an app. Keep following the track and it'll teach you.

Happy Coding! Good luck :)