Add bottle-song exercise (#437)

config.json

@@ -82,6 +82,14 @@
         ],
         "difficulty": 1
       },
+      {
+        "slug": "bottle-song",
+        "name": "Bottle Song",
+        "uuid": "26b6fdd5-6e9d-4a5a-87d3-e9de104b6f3d",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "square-root",
         "name": "Square Root",

exercises/practice/bottle-song/.docs/instructions.md

@@ -0,0 +1,57 @@
+# Instructions
+
+Recite the lyrics to that popular children's repetitive song: Ten Green Bottles.
+
+Note that not all verses are identical.
+
+```text
+Ten green bottles hanging on the wall,
+Ten green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be nine green bottles hanging on the wall.
+
+Nine green bottles hanging on the wall,
+Nine green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be eight green bottles hanging on the wall.
+
+Eight green bottles hanging on the wall,
+Eight green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be seven green bottles hanging on the wall.
+
+Seven green bottles hanging on the wall,
+Seven green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be six green bottles hanging on the wall.
+
+Six green bottles hanging on the wall,
+Six green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be five green bottles hanging on the wall.
+
+Five green bottles hanging on the wall,
+Five green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be four green bottles hanging on the wall.
+
+Four green bottles hanging on the wall,
+Four green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be three green bottles hanging on the wall.
+
+Three green bottles hanging on the wall,
+Three green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be two green bottles hanging on the wall.
+
+Two green bottles hanging on the wall,
+Two green bottles hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be one green bottle hanging on the wall.
+
+One green bottle hanging on the wall,
+One green bottle hanging on the wall,
+And if one green bottle should accidentally fall,
+There'll be no green bottles hanging on the wall.
+```

exercises/practice/bottle-song/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "bottle_song.zig"
+    ],
+    "test": [
+      "test_bottle_song.zig"
+    ],
+    "example": [
+      ".meta/example.zig"
+    ]
+  },
+  "blurb": "Produce the lyrics to the popular children's repetitive song: Ten Green Bottles.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Ten_Green_Bottles"
+}

exercises/practice/bottle-song/.meta/example.zig

@@ -0,0 +1,60 @@
+const std = @import("std");
+
+const green_bottle = " green bottle";
+
+const hanging_on = " hanging on the wall";
+
+const and_if = "And if one green bottle should accidentally fall,\nThere'll be ";
+
+const comma = ",\n";
+
+const stop = ".";
+
+const numbers = [_][]const u8{ "No", "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten" };
+
+fn appendString(buffer: []u8, offset: *usize, str: []const u8) void {
+    @memcpy(buffer[offset.*..(offset.* + str.len)], str);
+    offset.* += str.len;
+}
+
+fn appendLine(buffer: []u8, offset: *usize, num_bottles: u32) void {
+    appendString(buffer, offset, numbers[num_bottles]);
+
+    appendString(buffer, offset, green_bottle);
+
+    if (num_bottles != 1) {
+        buffer[offset.*] = 's';
+        offset.* += 1;
+    }
+
+    appendString(buffer, offset, hanging_on);
+}
+
+pub fn recite(buffer: []u8, start_bottles: u32, take_down: u32) []const u8 {
+    var offset: usize = 0;
+
+    var num_bottles = start_bottles;
+    while (num_bottles > start_bottles - take_down) {
+        if (num_bottles != start_bottles) {
+            buffer[offset] = '\n';
+            buffer[offset + 1] = '\n';
+            offset += 2;
+        }
+
+        appendLine(buffer, &offset, num_bottles);
+        appendString(buffer, &offset, comma);
+
+        appendLine(buffer, &offset, num_bottles);
+        appendString(buffer, &offset, comma);
+
+        appendString(buffer, &offset, and_if);
+        num_bottles -= 1;
+
+        const savedOffset = offset;
+        appendLine(buffer, &offset, num_bottles);
+        buffer[savedOffset] = buffer[savedOffset] | 32;
+        appendString(buffer, &offset, stop);
+    }
+
+    return buffer[0..offset];
+}

exercises/practice/bottle-song/.meta/tests.toml

@@ -0,0 +1,31 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[d4ccf8fc-01dc-48c0-a201-4fbeb30f2d03]
+description = "verse -> single verse -> first generic verse"
+
+[0f0aded3-472a-4c64-b842-18d4f1f5f030]
+description = "verse -> single verse -> last generic verse"
+
+[f61f3c97-131f-459e-b40a-7428f3ed99d9]
+description = "verse -> single verse -> verse with 2 bottles"
+
+[05eadba9-5dbd-401e-a7e8-d17cc9baa8e0]
+description = "verse -> single verse -> verse with 1 bottle"
+
+[a4a28170-83d6-4dc1-bd8b-319b6abb6a80]
+description = "lyrics -> multiple verses -> first two verses"
+
+[3185d438-c5ac-4ce6-bcd3-02c9ff1ed8db]
+description = "lyrics -> multiple verses -> last three verses"
+
+[28c1584a-0e51-4b65-9ae2-fbc0bf4bbb28]
+description = "lyrics -> multiple verses -> all verses"

exercises/practice/bottle-song/bottle_song.zig

@@ -0,0 +1,6 @@
+pub fn recite(buffer: []u8, start_bottles: u32, take_down: u32) []const u8 {
+    _ = buffer;
+    _ = start_bottles;
+    _ = take_down;
+    @compileError("please implement the recite function");
+}

exercises/practice/bottle-song/test_bottle_song.zig

@@ -0,0 +1,155 @@
+const std = @import("std");
+const testing = std.testing;
+
+const bottle_song = @import("bottle_song.zig");
+
+test "verse-single verse-first generic verse" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Ten green bottles hanging on the wall,
+        \\Ten green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be nine green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 10, 1);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "verse-single verse-last generic verse" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Three green bottles hanging on the wall,
+        \\Three green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be two green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 3, 1);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "verse-single verse-verse with 2 bottles" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Two green bottles hanging on the wall,
+        \\Two green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be one green bottle hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 2, 1);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "verse-single verse-verse with 1 bottle" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\One green bottle hanging on the wall,
+        \\One green bottle hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be no green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 1, 1);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "lyrics-multiple verses-first two verses" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Ten green bottles hanging on the wall,
+        \\Ten green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be nine green bottles hanging on the wall.
+        \\
+        \\Nine green bottles hanging on the wall,
+        \\Nine green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be eight green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 10, 2);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "lyrics-multiple verses-last three verses" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Three green bottles hanging on the wall,
+        \\Three green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be two green bottles hanging on the wall.
+        \\
+        \\Two green bottles hanging on the wall,
+        \\Two green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be one green bottle hanging on the wall.
+        \\
+        \\One green bottle hanging on the wall,
+        \\One green bottle hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be no green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 3, 3);
+    try testing.expectEqualStrings(expected, actual);
+}
+
+test "lyrics-multiple verses-all verses" {
+    const buffer_size = 4000;
+    var buffer: [buffer_size]u8 = undefined;
+    const expected: []const u8 =
+        \\Ten green bottles hanging on the wall,
+        \\Ten green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be nine green bottles hanging on the wall.
+        \\
+        \\Nine green bottles hanging on the wall,
+        \\Nine green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be eight green bottles hanging on the wall.
+        \\
+        \\Eight green bottles hanging on the wall,
+        \\Eight green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be seven green bottles hanging on the wall.
+        \\
+        \\Seven green bottles hanging on the wall,
+        \\Seven green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be six green bottles hanging on the wall.
+        \\
+        \\Six green bottles hanging on the wall,
+        \\Six green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be five green bottles hanging on the wall.
+        \\
+        \\Five green bottles hanging on the wall,
+        \\Five green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be four green bottles hanging on the wall.
+        \\
+        \\Four green bottles hanging on the wall,
+        \\Four green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be three green bottles hanging on the wall.
+        \\
+        \\Three green bottles hanging on the wall,
+        \\Three green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be two green bottles hanging on the wall.
+        \\
+        \\Two green bottles hanging on the wall,
+        \\Two green bottles hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be one green bottle hanging on the wall.
+        \\
+        \\One green bottle hanging on the wall,
+        \\One green bottle hanging on the wall,
+        \\And if one green bottle should accidentally fall,
+        \\There'll be no green bottles hanging on the wall.
+    ;
+    const actual = bottle_song.recite(&buffer, 10, 10);
+    try testing.expectEqualStrings(expected, actual);
+}