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

J. Tigre
PLUS
J. Tigre
Courses Plus Student 2,845 Points

How to use the value of counter using a var index to compute the sum of the values in the array?

I tried to use the unary operator += to .count to prevent to loop to running infinitely. Please help!

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 {

  counter += 1 
  index += counter
}
J. Tigre
J. Tigre
Courses Plus Student 2,845 Points

How do I use the value of counter as an index? How do I retrieve each value from the array and add to the value of sum?

Peter Correa
Peter Correa
17,155 Points

Remember that the index of an array begins with 0. Thus, the counter will need to decrease by a value of 1 to equal the relative index position of that value in the array. After you have that, you can use the index to continually compound the sum of each element in the array.

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

// Enter your code below
while counter < numbers.count {
    counter += 1
    var index = (counter - 1)
    sum = numbers[index] + sum
}

print(sum)