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# Why does the ++Index operator start at 0 and not 1 in this for loop?

When this loop runs, it prints the value of 0 first, instead of printing 1 The initializer is set to 0, however the ++Index should be 1? I am confused

```var index: Int
for index = 0; index < 3; ++index {
print("index is \(index)")
}
// index is 0
// index is 1
// index is 2
print("The loop statements were executed \(index) times")
// prints "The loop statements were executed 3 times"
```

The three parameters you use in your for loop are counter, qualifier, incrementor.

• It starts the loop with the counter value, which is 0
• Evaluates the loop conditional, which is less than 3
• Then does the loop printing the counter at 0
• Completes the loop, then applies the incrementor
• Loops and evaluates 1 is less than 3
• Then does the loop again printing counter at 1
• Completes the loop, then applies the incrementor
• Loops and evaluates 2 is less than 3
• Then does the loop again printing counter at 2
• Completes the loop, then applies the incrementor
• Loops and evaluates 3 is not less than 3
• Ends the for loop

Makes sense?

The increment portion of the for loop happens at the end of the each iteration. So translated to the while loop you would get the following

```var index: Int = 0

while index < 3 {
print("index is \(index)") // index is still 0 here
++index // index is now 1
}
```