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

Hadi Farhat
PLUS
Hadi Farhat
Courses Plus Student 7,102 Points

I still didn't understand why Amit placed the index in : println(todo[index])

why should we put index beside todo in order for the code to work correctly ?

2 Answers

Jhoan Arango
Jhoan Arango
14,350 Points

Hello:

Here you are creating a while loop. Remember that a while loop will continue working until it becomes FALSE.

let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] // Array of 10 numbers, so 
// index is from 0 to 9

var index = 0 // Here we are giving a value of 0 to a variable

while index < numbers.count {println(numbers[index]) // while the variable index is 
//less than the total numbers in the array, then print a number from the array

index++ // Add one to index, and repeat the process until it becomes false. 
}

Here is how it looks without all the comments.

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

var index = 0 
while index < numbers.count {println(numbers[index]) 
index++
}
chunchang pan
chunchang pan
4,319 Points

var todo: [String] = ["Learn Swift", "Build App", "Deploy App"]<br>

func printlnLoop(s:[String]) ->()<br> {<br> var index: Int = 0<br> for s in todo<br> {<br> println("Index is \(index) and value is \(s)")<br> index++<br> }<br> println("===========================================")<br>

```printlnLoop(todo)```<br>

 hope this sample code can help you understand  the concept of array