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iOS Swift Collections and Control Flow Control Flow With Loops Working With Loops

George Gregorczyk
George Gregorczyk
3,028 Points
Posted by George Gregorczyk
George Gregorczyk
3,028 Points

while loop

I'm having trouble with that question

loops.swift 
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below

while counter < numbers.count { 
  sum = sum + counter[numbers]
  counter += 1
}

2 Answers

Steven Parker
Steven Parker
228,039 Points
Steven Parker
Steven Parker
228,039 Points

When retrieving an item from an array, put the array name first, and then the index inside the brackets:

//sum = sum + counter[numbers]  <-- instead of this ...
  sum = sum + numbers[counter]  //  do this
Thomas Oliver Bastable
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Thomas Oliver Bastable
iOS Development Techdegree Graduate 22,672 Points
Thomas Oliver Bastable
.a{fill-rule:evenodd;}techdegree seal-36
Thomas Oliver Bastable
iOS Development Techdegree Graduate 22,672 Points

Your issue lays in the below line

sum = sum + counter[numbers]

You've got the numbers array confused with the counter. It should be the other way around - the below code should work. Hope this helps.

while counter < numbers.count{
  sum += numbers[counter]
  counter += 1
}