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//
// The tricky part is that the pointer's mutability (var vs const) refers
// to the ability to change what the pointer POINTS TO, not the ability
// to change the VALUE at that location!
//
// const locked: u8 = 5;
// var unlocked: u8 = 10;
//
// const p1: *const u8 = &locked;
// var p2: *const u8 = &locked;
//
// Both p1 and p2 point to constant values which cannot change. However,
// p2 can be changed to point to something else and p1 cannot!
//
// const p3: *u8 = &unlocked;
// var p4: *u8 = &unlocked;
// const p5: *const u8 = &unlocked;
// var p6: *const u8 = &unlocked;
//
// Here p3 and p4 can both be used to change the value they point to but
// p3 cannot point at anything else.
// What's interesting is that p5 and p6 act like p1 and p2, but point to
// the value at "unlocked". This is what we mean when we say that we can
// make a constant reference to any value!
//
const std = @import("std");
pub fn main() void {
var foo: u8 = 5;
var bar: u8 = 10;
// Please define pointer "p" so that it can point to EITHER foo or
// bar AND change the value it points to!
??? p: ??? = undefined;
p = &foo;
p.* += 1;
p = &bar;
p.* += 1;
std.debug.print("foo={}, bar={}\n", .{foo, bar});
}
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