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

Jake N
Jake N
612 Points
Posted by Jake N
Jake N
612 Points

what am i messing up

while numbers < numbers,count { println(numbers[index]) index ++ }

while_loops.swift 
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
while numbers < todo.count {
println(todo[numbers])
numbers ++
}
Jeroen de Vrind
Jeroen de Vrind
29,772 Points
Jeroen de Vrind
Jeroen de Vrind
29,772 Points

You need to set a new variable to count the component of the array you're printing like an Int i. You use 'numbers' and that's the array itself. you have to increment this variable i within the loop. The loop will repeat until this variable achieves the same value as the number of elements in the array 'numbers'. I don't know why u use the variable todo, cause you didn't declare it in your code, you need to get the count property of the numbers array. Like in the println you need to get the position i in the numbers array. I give you my solution:

let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
var i :Int = 0
while i<numbers.count {
println(numbers[i])
i++
}

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Here is what you have wrong : You have to change the “todo.count” to “numbers.count”

// remember that an array has index, 
// numbers[0] <-- index 0 is the number 1 in your array

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

var index = 0 // create a variable with an initial value of 0

//the loop will work until is FALSE

while index < numbers.count { // while the var INDEX is less than the total of elements in your array then do the following
    println(numbers[index]) // print the first number of the array (numbers[0])
    index++ // now increment the variable INDEX by one and start again
}

this is what it looks like without 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++ 
}