ziglings/exercises/04_arrays.zig
2021-02-14 15:42:42 +13:00

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Zig

//
// Let's learn some array basics. Arrays are declared with:
//
// var foo: [3]u32 = [3]u32{ 42, 108, 5423 };
//
// When Zig can infer the size of the array, you can use '_' for the
// size. You can also let Zig infer the type of the value so the
// declaration is much less verbose.
//
// var foo = [_]u32{ 42, 108, 5423 };
//
// Get values of an array using array[index] notation:
//
// const bar = foo[2]; // 5423
//
// Set values of an array using array[index] notation:
//
// foo[2] = 16;
//
// Get the length of an array using the len property:
//
// const length = foo.len;
//
const std = @import("std");
pub fn main() void {
// (Problem 1)
// This "const" is going to cause a problem later - can you see what it is?
// How do we fix it?
const some_primes = [_]u8{ 1, 3, 5, 7, 11, 13, 17, 19 };
// Individual values can be set with '[]' notation.
// Example: This line changes the first prime to 2 (which is correct):
some_primes[0] = 2;
// Individual values can also be accessed with '[]' notation.
// Example: This line stores the first prime in "first":
const first = some_primes[0];
// (Problem 2)
// Looks like we need to complete this expression. Use the example
// above to set "fourth" to the fourth element of the some_primes array:
const fourth = some_primes[???];
// (Problem 3)
// Use the len property to get the length of the array:
const length = some_primes.???;
std.debug.print("First: {}, Fourth: {}, Length: {}\n",
.{first, fourth, length});
}