Learn ZIG with Real Code Examples

const std = @import("std");
var count: i32 = 0;
var isDark: bool = false;

fn updateUI() void {
    std.debug.print("Counter: {d}\n", .{count});
    std.debug.print("Theme: {s}\n", .{ if (isDark) "Dark" else "Light" });
}

fn increment() void {
    count += 1;
    updateUI();
}

fn decrement() void {
    count -= 1;
    updateUI();
}

fn reset() void {
    count = 0;
    updateUI();
}

fn toggleTheme() void {
    isDark = !isDark;
    updateUI();
}

pub fn main() void {
    updateUI();
    increment();
    increment();
    toggleTheme();
    decrement();
    reset();
}

Demonstrates a simple counter with theme toggling using Zig variables and functions.

const std = @import("std");

pub fn main() void {
    var rng = std.rand.DefaultPrng.init(std.time.nanoTimestamp());
    for (0..3) |i| {
        const num = rng.random.int(i32) % 100 + 1;
        std.debug.print("Random #{d}: {d}\n", .{i+1, num});
    }
}

Generates random numbers between 1 and 100.

const std = @import("std");
var todos: [10]?[]const u8 = [_]?[]const u8{null} ** 10;
var count: usize = 0;

fn addTask(task: []const u8) void {
    if (count < todos.len) {
        todos[count] = task;
        count += 1;
    }
}

fn removeTask(index: usize) void {
    if (index < count) {
        for (index..count-1) |i| {
        todos[i] = todos[i+1];
        }
        count -= 1;
    }
}

fn printTasks() void {
    for (0..count) |i| {
        std.debug.print("{d}: {s}\n", .{i+1, todos[i]});
    }
    std.debug.print("----------------\n", .{});
}

pub fn main() void {
    addTask("Buy milk");
    addTask("Write Zig code");
    printTasks();
    removeTask(0);
    printTasks();
}

Adds and removes tasks from a todo list.

const std = @import("std");

pub fn main() void {
    var rng = std.rand.DefaultPrng.init(std.time.nanoTimestamp());
    for (0..3) |i| {
        const roll = rng.random.int(u32) % 6 + 1;
        std.debug.print("Roll #{d}: {d}\n", .{i+1, roll});
    }
}

Rolls a six-sided dice three times.

const std = @import("std");

pub fn main() void {
    var count: i32 = 5;
    while (count >= 0) : (count -= 1) {
        std.debug.print("Countdown: {d}\n", .{count});
    }
    std.debug.print("Done!\n", .{});
}

Counts down from 5 to 0.

const std = @import("std");

fn isPrime(n: u32) bool {
    if (n < 2) return false;
    for (2..std.math.sqrtInt(u32, n)+1) |i| {
        if (n % i == 0) return false;
    }
    return true;
}

pub fn main() void {
    const nums: [3]u32 = [3]u32{7, 10, 13};
    for (nums) |num| {
        std.debug.print("{d} is {s}\n", .{num, if (isPrime(num)) "Prime" else "Not Prime"});
    }
}

Checks if numbers are prime.

const std = @import("std");

fn cToF(c: f64) f64 { return c * 9.0 / 5.0 + 32.0; }
fn fToC(f: f64) f64 { return (f - 32.0) * 5.0 / 9.0; }

pub fn main() void {
    std.debug.print("25°C = {f}°F\n", .{cToF(25.0)});
    std.debug.print("77°F = {f}°C\n", .{fToC(77.0)});
}

Converts Celsius to Fahrenheit and Fahrenheit to Celsius.

const std = @import("std");
var items: [5]?[]const u8 = [_]?[]const u8{null} ** 5;
var prices: [5]f64 = [_]f64{0} ** 5;
var count: usize = 0;
var total: f64 = 0;

fn addItem(item: []const u8, price: f64) void {
    if (count < items.len) {
        items[count] = item;
        prices[count] = price;
        total += price;
        count += 1;
    }
}

fn removeItem(index: usize) void {
    if (index < count) {
        total -= prices[index];
        for (index..count-1) |i| {
        items[i] = items[i+1];
        prices[i] = prices[i+1];
        }
        count -= 1;
    }
}

fn printCart() void {
    for (0..count) |i| {
        std.debug.print("{s}: ${f}\n", .{items[i], prices[i]});
    }
    std.debug.print("Total: ${f}\n----------------\n", .{total});
}

pub fn main() void {
    addItem("Apple", 2.0);
    addItem("Banana", 3.0);
    printCart();
    removeItem(0);
    printCart();
}

Adds and removes items in a shopping cart with total cost.

const std = @import("std");

fn greet(name: []const u8) void {
    std.debug.print("Hello, {s}! Welcome!\n", .{name});
}

pub fn main() void {
    greet("Saurav");
    greet("Alice");
    greet("Bob");
}

Greets users by name.

const std = @import("std");

pub fn main() void {
    var time: i32 = 0;
    while (time < 5) : (time += 1) {
        std.debug.print("Stopwatch: {d} seconds\n", .{time});
    }
    std.debug.print("Done!\n", .{});
}

Simulates a stopwatch by incrementing seconds.