mirror of
https://codeberg.org/ziglings/exercises.git
synced 2025-10-30 18:25:36 +00:00
55 lines
1.7 KiB
Zig
55 lines
1.7 KiB
Zig
//
|
|
// We've seen that passing arrays around can be awkward. Perhaps you
|
|
// remember a particularly horrendous function definition from quiz3?
|
|
// This function can only take arrays that are exactly 4 items long!
|
|
//
|
|
// fn printPowersOfTwo(numbers: [4]u16) void { ... }
|
|
//
|
|
// That's the trouble with arrays - their size is part of the data
|
|
// type and must be hard-coded into every usage of that type. This
|
|
// digits array is a [10]u8 forever and ever:
|
|
//
|
|
// var digits = [10]u8{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
|
|
//
|
|
// Thankfully, Zig has slices, which let you dynamically point to a
|
|
// start item and provide a length. Here are slices of our digit
|
|
// array:
|
|
//
|
|
// const foo = digits[0..1]; // 0
|
|
// const bar = digits[3..9]; // 3 4 5 6 7 8
|
|
// const baz = digits[5..9]; // 5 6 7 8
|
|
// const all = digits[0..]; // 0 1 2 3 4 5 6 7 8 9
|
|
//
|
|
// As you can see, a slice [x..y] starts with the index of the
|
|
// first item at x and the last item at y-1. You can leave the y
|
|
// off to get "the rest of the items".
|
|
//
|
|
// The type of a slice on an array of u8 items is []u8.
|
|
//
|
|
const std = @import("std");
|
|
|
|
pub fn main() void {
|
|
var cards = [8]u8{ 'A', '4', 'K', '8', '5', '2', 'Q', 'J' };
|
|
|
|
// Please put the first 4 cards in hand1 and the rest in hand2.
|
|
const hand1: []u8 = cards[???];
|
|
const hand2: []u8 = cards[???];
|
|
|
|
std.debug.print("Hand1: ", .{});
|
|
printHand(hand1);
|
|
|
|
std.debug.print("Hand2: ", .{});
|
|
printHand(hand2);
|
|
}
|
|
|
|
// Please lend this function a hand. A u8 slice hand, that is.
|
|
fn printHand(hand: ???) void {
|
|
for (hand) |h| {
|
|
std.debug.print("{u} ", .{h});
|
|
}
|
|
std.debug.print("\n", .{});
|
|
}
|
|
//
|
|
// Fun fact: Under the hood, slices are stored as a pointer to
|
|
// the first item and a length.
|