Initial commit

build.zig

@@ -0,0 +1,91 @@
+const std = @import("std");
+
+// Although this function looks imperative, note that its job is to
+// declaratively construct a build graph that will be executed by an external
+// runner.
+pub fn build(b: *std.Build) void {
+    // Standard target options allows the person running `zig build` to choose
+    // what target to build for. Here we do not override the defaults, which
+    // means any target is allowed, and the default is native. Other options
+    // for restricting supported target set are available.
+    const target = b.standardTargetOptions(.{});
+
+    // Standard optimization options allow the person running `zig build` to select
+    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
+    // set a preferred release mode, allowing the user to decide how to optimize.
+    const optimize = b.standardOptimizeOption(.{});
+
+    // const lib = b.addStaticLibrary(.{
+    //     .name = "divisors",
+    //     // In this case the main source file is merely a path, however, in more
+    //     // complicated build scripts, this could be a generated file.
+    //     .root_source_file = b.path("src/root.zig"),
+    //     .target = target,
+    //     .optimize = optimize,
+    // });
+
+    // This declares intent for the library to be installed into the standard
+    // location when the user invokes the "install" step (the default step when
+    // running `zig build`).
+    // b.installArtifact(lib);
+
+    const exe = b.addExecutable(.{
+        .name = "divisors",
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    // This declares intent for the executable to be installed into the
+    // standard location when the user invokes the "install" step (the default
+    // step when running `zig build`).
+    b.installArtifact(exe);
+
+    // This *creates* a Run step in the build graph, to be executed when another
+    // step is evaluated that depends on it. The next line below will establish
+    // such a dependency.
+    const run_cmd = b.addRunArtifact(exe);
+
+    // By making the run step depend on the install step, it will be run from the
+    // installation directory rather than directly from within the cache directory.
+    // This is not necessary, however, if the application depends on other installed
+    // files, this ensures they will be present and in the expected location.
+    run_cmd.step.dependOn(b.getInstallStep());
+
+    // This allows the user to pass arguments to the application in the build
+    // command itself, like this: `zig build run -- arg1 arg2 etc`
+    if (b.args) |args| {
+        run_cmd.addArgs(args);
+    }
+
+    // This creates a build step. It will be visible in the `zig build --help` menu,
+    // and can be selected like this: `zig build run`
+    // This will evaluate the `run` step rather than the default, which is "install".
+    const run_step = b.step("run", "Run the app");
+    run_step.dependOn(&run_cmd.step);
+
+    // Creates a step for unit testing. This only builds the test executable
+    // but does not run it.
+    // const lib_unit_tests = b.addTest(.{
+    //     .root_source_file = b.path("src/root.zig"),
+    //     .target = target,
+    //     .optimize = optimize,
+    // });
+
+    // const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);
+
+    const exe_unit_tests = b.addTest(.{
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);
+
+    // Similar to creating the run step earlier, this exposes a `test` step to
+    // the `zig build --help` menu, providing a way for the user to request
+    // running the unit tests.
+    const test_step = b.step("test", "Run unit tests");
+    // test_step.dependOn(&run_lib_unit_tests.step);
+    test_step.dependOn(&run_exe_unit_tests.step);
+}

src/main.zig

@@ -0,0 +1,44 @@
+const std = @import("std");
+
+pub fn main() !void {
+    const n: i32 = -27;
+    const res = try getMostDivisors(n);
+    defer res.deinit();
+
+    if (res.items.len == 0) return;
+
+    const stdout = std.io.getStdOut().writer();
+    try stdout.print("From 1 to {d}, {d} has the most ({d}) divisors:\n[", .{ n, res.items[res.items.len - 1], res.items.len });
+    const last_item = res.items[res.items.len - 1];
+    var chr = ", ";
+
+    for (res.items) |i| {
+        if (i == last_item) chr = "]\n";
+        try stdout.print("{d}{s}", .{ i, chr });
+    }
+}
+
+fn getMostDivisors(n: i32) !std.ArrayList(usize) {
+    const nc: usize = @intCast(@abs(n));
+    const allocator = std.heap.page_allocator;
+    var res = std.ArrayList(usize).init(allocator);
+
+    for (1..nc + 1) |i| {
+        const div = try getDivisors(allocator, i);
+        if (div.items.len > res.items.len) {
+            res = div;
+        }
+    }
+
+    return res;
+}
+
+fn getDivisors(alloc: std.mem.Allocator, n: usize) !std.ArrayList(usize) {
+    var divs = std.ArrayList(usize).init(alloc);
+
+    for (1..n + 1) |i| {
+        if (n % i == 0) try divs.append(i);
+    }
+
+    return divs;
+}

src/root.zig

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+const std = @import("std");
+const testing = std.testing;
+
+export fn add(a: i32, b: i32) i32 {
+    return a + b;
+}
+
+test "basic add functionality" {
+    try testing.expect(add(3, 7) == 10);
+}