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

Posted by Neymat Kakar
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Neymat Kakar
iOS Development Techdegree Student 786 Points

collections and control flow

Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.

For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array.

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

// Enter your code below
numbers.count
while counter < numbers.count
{
var newValue = numbers[newValue]

sum = sum + newValue 

counter += 1
}
//counter = numbers[counter]
//sum = sum + counter
//print (numbers[counter])

//counter += 1
Neymat Kakar
.a{fill-rule:evenodd;}techdegree
Neymat Kakar
iOS Development Techdegree Student 786 Points

below is the code i provided which did not work. if anyone knows the answer plz?

1 Answer

Jorge Solana
Jorge Solana
6,064 Points

Hey Neymat!

If you do that counter = numbers [counter] part, you screw the counter variable which is our index to read from first to last members of the numbers array. Counter is meant to indicate our position in the array.

If variable sum has to add each value from the array in that position, we should just do something like this:

sum += numbers [counter]
counter += 1

With the code you provide you do the exact same thing, but then counter loses its use as an index and we won't be able to read all the values in the array.

Hope It helps!