Swap two ints

Goal

Fill in Swap so it swaps the values that a and b point to.

Example

x, y := 3, 9
Swap(&x, &y)
fmt.Println(x, y) // 9 3

x, y = 5, 5
Swap(&x, &y)
fmt.Println(x, y) // 5 5

Rules

• Edit swap.go. The function has a // TODO comment and currently does nothing.
• Swap the values through the pointers — a and b themselves don't change, but what they point to does.
• Handle the case where a and b point to the same variable: the value there should be unchanged afterward.
• Do not change the line func Swap(a, b *int) {. Do not add imports.

What you'll practice

Reading and writing through two pointers in the same function, and keeping a swap correct even when both pointers point to the same place.

Run it

gonomicon fetch week-1/13-02-swap-two-ints
cd 13-02-swap-two-ints
gonomicon test
gonomicon submit

Hints

1. You can't just write a, b = b, a here — a and b are pointers, so that would swap the pointers themselves, not the values they point to. You need *a and *b.
2. Save *a somewhere before you overwrite it, the same way you'd swap two cups of water using a third empty cup.
3. tmp := *a *a = *b *b = tmp