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Mohammed Abushamala
3,650 PointsCan someone tell me why is this wrong for While loop? why is the equal sign in the while condition is wrong
let numbers = [2,8,1,16,4,3,9] var sum = 0 var counter = 0
// Enter your code below while counter <= numbers.count { sum += numbers[counter] print(sum) counter += 1 }
1 Answer
Jennifer Nordell
Treehouse TeacherHi there! A good percentage of programming languages out there have what we call "0 indexed arrays" and this means that they start counting at 0. Your counter also starts at 0, which is handy. But the count method counts like humans. It's looking at that array and counting the number of items there. In this example, there are 7 numbers in the array. So your while loop will go while count is less than or equal to 7. At the last iteration, it will try to access the array at index 7. We have 2 at index 0, 8 at index 1... etc. If you count up, you'll see that the last possible number is at array index 6. When it tries to access index 7, it will produce an error as that is outside the bounds of the current array. So what you want to do is count upwards from 0 while counter is less than the count of the array.
Hope this helps!
