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

Mia Pivirotto
Mia Pivirotto
5,557 Points
Posted by Mia Pivirotto
Mia Pivirotto
5,557 Points

Why does the index++ in the while and do while loops stop the program from going on forever and make it go only 5 times?

I guess I just don't understand the whole concept of the while and do while loops, what exactly are we accomplishing with them?

1 Answer

Roberto Alicata
PLUS
Roberto Alicata
Courses Plus Student 39,959 Points
Roberto Alicata
Roberto Alicata
Courses Plus Student 39,959 Points

"index++" is equal to write "index = index + 1". It is used like a counter to test if the cicle have to run again or not (when you test index < todo.count )

The first time the program test the condition (index < todo.count) index is equal 0.

Then within the loop index is incremented by 1 (index++).

Then the while loop starts again and test index < todo.count and index now is equal 1... and so on.

When index is equal todo.count the while loop doesn't start.