2022-05 in zig

2022/05-supply-stacks/example

@@ -0,0 +1,10 @@
+    [D]    
+[N] [C]    
+[Z] [M] [P]
+ 1   2   3 
+
+move 1 from 2 to 1
+move 3 from 1 to 3
+move 2 from 2 to 1
+move 1 from 1 to 2
+

2022/05-supply-stacks/first.zig

@@ -0,0 +1,62 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    var output = try solve(example, allocator);
+    try std.testing.expect(std.mem.eql(u8, output, "CMZ"));
+
+    const result = try solve(input, allocator);
+    try std.io.getStdOut().writer().print("{s}\n", .{result});
+}
+
+fn solve(puzzle: []const u8, allocator: std.mem.Allocator) ![]u8 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var line = it.next() orelse unreachable;
+    // Initializations from the first line
+    const size = (line.len + 1) / 4;
+    var output = try allocator.alloc(u8, size);
+    var stacks = try allocator.alloc(std.ArrayList(u8), size);
+    for (stacks) |*stack| {
+        stack.* = std.ArrayList(u8).init(allocator);
+    }
+    // parse stacks
+    while (true) {
+        var i: usize = 0;
+        while (i < size) : (i += 1) {
+            const v = line[i * 4 + 1];
+            if (v != ' ') {
+                try stacks[i].insert(0, v);
+            }
+        }
+        line = it.next() orelse unreachable;
+        if (line[0] != '[') { // we got the line with numbers
+            break;
+        }
+    }
+    // process rules
+    while (it.next()) |l| {
+        var elts = std.mem.split(u8, l, " ");
+        _ = elts.next() orelse unreachable; // the move word
+        var n = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10);
+        _ = elts.next() orelse unreachable; // the from word
+        const s = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10) - 1;
+        _ = elts.next() orelse unreachable; // the to word
+        const d = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10) - 1;
+        while (n > 0) : (n -= 1) {
+            const v = stacks[s].pop();
+            try stacks[d].append(v);
+        }
+    }
+    // generate output
+    var i: usize = 0;
+    while (i < size) : (i += 1) {
+        output[i] = stacks[i].pop();
+    }
+    return output;
+}

2022/05-supply-stacks/input

@@ -0,0 +1,514 @@
+[N]         [C]     [Z]            
+[Q] [G]     [V]     [S]         [V]
+[L] [C]     [M]     [T]     [W] [L]
+[S] [H]     [L]     [C] [D] [H] [S]
+[C] [V] [F] [D]     [D] [B] [Q] [F]
+[Z] [T] [Z] [T] [C] [J] [G] [S] [Q]
+[P] [P] [C] [W] [W] [F] [W] [J] [C]
+[T] [L] [D] [G] [P] [P] [V] [N] [R]
+ 1   2   3   4   5   6   7   8   9 
+
+move 6 from 2 to 1
+move 4 from 6 to 3
+move 1 from 6 to 5
+move 8 from 3 to 8
+move 13 from 8 to 2
+move 2 from 7 to 6
+move 10 from 1 to 6
+move 3 from 2 to 8
+move 5 from 4 to 2
+move 15 from 6 to 5
+move 1 from 1 to 4
+move 2 from 7 to 3
+move 2 from 4 to 2
+move 12 from 5 to 1
+move 4 from 8 to 9
+move 15 from 1 to 3
+move 10 from 9 to 7
+move 1 from 5 to 1
+move 1 from 4 to 8
+move 3 from 7 to 6
+move 8 from 2 to 6
+move 1 from 9 to 8
+move 5 from 2 to 3
+move 1 from 4 to 1
+move 16 from 3 to 1
+move 2 from 2 to 7
+move 13 from 1 to 6
+move 1 from 2 to 4
+move 2 from 2 to 9
+move 1 from 4 to 7
+move 2 from 8 to 2
+move 2 from 2 to 9
+move 1 from 6 to 8
+move 2 from 3 to 8
+move 2 from 1 to 9
+move 1 from 3 to 9
+move 1 from 3 to 2
+move 5 from 5 to 1
+move 2 from 9 to 3
+move 1 from 2 to 3
+move 2 from 1 to 3
+move 3 from 3 to 2
+move 1 from 5 to 7
+move 2 from 7 to 6
+move 2 from 8 to 3
+move 1 from 8 to 9
+move 6 from 3 to 4
+move 3 from 9 to 6
+move 8 from 6 to 4
+move 1 from 2 to 3
+move 1 from 2 to 6
+move 1 from 2 to 9
+move 1 from 3 to 9
+move 5 from 9 to 5
+move 7 from 7 to 4
+move 14 from 4 to 6
+move 1 from 5 to 3
+move 5 from 1 to 9
+move 4 from 5 to 4
+move 1 from 1 to 7
+move 1 from 3 to 8
+move 1 from 8 to 4
+move 4 from 9 to 7
+move 6 from 6 to 5
+move 10 from 4 to 6
+move 1 from 9 to 6
+move 1 from 4 to 3
+move 1 from 3 to 6
+move 1 from 4 to 2
+move 35 from 6 to 3
+move 1 from 2 to 3
+move 4 from 5 to 8
+move 2 from 5 to 4
+move 3 from 8 to 2
+move 2 from 4 to 8
+move 26 from 3 to 8
+move 3 from 2 to 9
+move 6 from 3 to 5
+move 3 from 5 to 7
+move 3 from 7 to 4
+move 3 from 4 to 5
+move 1 from 9 to 5
+move 6 from 5 to 1
+move 2 from 8 to 6
+move 11 from 8 to 5
+move 9 from 5 to 4
+move 1 from 9 to 7
+move 2 from 7 to 9
+move 3 from 1 to 4
+move 1 from 5 to 7
+move 8 from 6 to 1
+move 5 from 7 to 9
+move 7 from 9 to 2
+move 3 from 2 to 9
+move 3 from 7 to 1
+move 4 from 9 to 8
+move 2 from 5 to 6
+move 2 from 2 to 8
+move 2 from 6 to 9
+move 13 from 8 to 1
+move 1 from 2 to 8
+move 3 from 3 to 5
+move 1 from 9 to 8
+move 3 from 5 to 4
+move 1 from 9 to 3
+move 1 from 2 to 3
+move 4 from 8 to 2
+move 3 from 2 to 4
+move 19 from 1 to 2
+move 8 from 1 to 8
+move 1 from 4 to 3
+move 1 from 4 to 1
+move 7 from 2 to 1
+move 1 from 3 to 1
+move 2 from 3 to 1
+move 15 from 4 to 5
+move 1 from 1 to 7
+move 11 from 2 to 8
+move 2 from 2 to 9
+move 1 from 3 to 5
+move 2 from 9 to 4
+move 12 from 8 to 3
+move 16 from 5 to 1
+move 3 from 4 to 3
+move 1 from 7 to 5
+move 2 from 8 to 6
+move 1 from 5 to 4
+move 1 from 4 to 9
+move 18 from 1 to 9
+move 8 from 3 to 8
+move 9 from 8 to 2
+move 4 from 9 to 2
+move 8 from 1 to 2
+move 2 from 6 to 4
+move 17 from 2 to 1
+move 1 from 4 to 5
+move 3 from 2 to 6
+move 1 from 2 to 9
+move 2 from 6 to 1
+move 3 from 3 to 6
+move 1 from 4 to 6
+move 2 from 3 to 2
+move 16 from 9 to 5
+move 14 from 5 to 4
+move 3 from 5 to 8
+move 1 from 2 to 4
+move 4 from 8 to 6
+move 1 from 2 to 8
+move 1 from 3 to 9
+move 1 from 3 to 9
+move 2 from 9 to 1
+move 10 from 8 to 7
+move 7 from 6 to 9
+move 16 from 1 to 5
+move 7 from 4 to 3
+move 1 from 8 to 4
+move 5 from 4 to 2
+move 1 from 5 to 9
+move 5 from 9 to 1
+move 5 from 1 to 2
+move 2 from 9 to 7
+move 1 from 1 to 7
+move 1 from 6 to 8
+move 4 from 4 to 5
+move 1 from 6 to 9
+move 9 from 2 to 1
+move 11 from 5 to 6
+move 2 from 9 to 2
+move 4 from 3 to 4
+move 4 from 4 to 6
+move 1 from 3 to 4
+move 11 from 7 to 4
+move 9 from 4 to 7
+move 11 from 7 to 2
+move 2 from 3 to 5
+move 2 from 4 to 8
+move 7 from 5 to 2
+move 1 from 8 to 3
+move 1 from 5 to 1
+move 1 from 3 to 7
+move 6 from 2 to 9
+move 1 from 8 to 9
+move 6 from 9 to 2
+move 15 from 6 to 2
+move 1 from 7 to 2
+move 31 from 2 to 7
+move 22 from 7 to 3
+move 2 from 5 to 1
+move 3 from 7 to 4
+move 1 from 4 to 9
+move 3 from 4 to 3
+move 1 from 8 to 6
+move 1 from 9 to 6
+move 15 from 1 to 5
+move 1 from 9 to 5
+move 1 from 1 to 8
+move 2 from 6 to 8
+move 1 from 8 to 4
+move 1 from 4 to 6
+move 1 from 6 to 9
+move 10 from 3 to 1
+move 1 from 9 to 7
+move 2 from 7 to 8
+move 10 from 5 to 1
+move 12 from 1 to 4
+move 1 from 3 to 8
+move 11 from 4 to 8
+move 1 from 8 to 3
+move 5 from 5 to 8
+move 1 from 5 to 8
+move 6 from 8 to 6
+move 3 from 2 to 1
+move 1 from 6 to 2
+move 5 from 1 to 6
+move 3 from 1 to 4
+move 3 from 2 to 8
+move 1 from 2 to 9
+move 8 from 3 to 5
+move 2 from 1 to 3
+move 3 from 7 to 5
+move 2 from 3 to 5
+move 3 from 5 to 2
+move 1 from 7 to 9
+move 2 from 9 to 1
+move 1 from 6 to 9
+move 2 from 4 to 8
+move 5 from 6 to 5
+move 1 from 6 to 7
+move 1 from 9 to 8
+move 3 from 6 to 5
+move 7 from 8 to 9
+move 5 from 9 to 1
+move 2 from 4 to 8
+move 11 from 5 to 9
+move 3 from 2 to 3
+move 2 from 5 to 8
+move 4 from 3 to 7
+move 11 from 9 to 5
+move 3 from 7 to 5
+move 1 from 3 to 5
+move 8 from 1 to 4
+move 5 from 3 to 9
+move 15 from 5 to 4
+move 8 from 4 to 1
+move 12 from 8 to 1
+move 4 from 5 to 8
+move 12 from 4 to 5
+move 3 from 7 to 2
+move 11 from 5 to 7
+move 8 from 8 to 7
+move 7 from 9 to 8
+move 2 from 5 to 7
+move 4 from 7 to 8
+move 9 from 8 to 4
+move 11 from 4 to 5
+move 6 from 7 to 8
+move 9 from 8 to 7
+move 18 from 7 to 5
+move 1 from 8 to 1
+move 4 from 1 to 5
+move 1 from 7 to 2
+move 6 from 1 to 9
+move 1 from 2 to 4
+move 1 from 4 to 3
+move 3 from 1 to 7
+move 1 from 4 to 2
+move 3 from 2 to 5
+move 2 from 9 to 5
+move 1 from 2 to 6
+move 4 from 7 to 8
+move 1 from 6 to 2
+move 1 from 2 to 4
+move 4 from 8 to 5
+move 3 from 9 to 7
+move 1 from 9 to 5
+move 1 from 4 to 3
+move 2 from 3 to 8
+move 2 from 7 to 4
+move 28 from 5 to 8
+move 1 from 8 to 9
+move 1 from 9 to 3
+move 6 from 5 to 6
+move 5 from 5 to 2
+move 1 from 3 to 4
+move 1 from 7 to 4
+move 1 from 5 to 6
+move 16 from 8 to 3
+move 7 from 1 to 8
+move 4 from 4 to 9
+move 1 from 2 to 4
+move 3 from 2 to 3
+move 6 from 6 to 8
+move 10 from 3 to 8
+move 1 from 2 to 7
+move 1 from 6 to 7
+move 11 from 8 to 5
+move 2 from 7 to 8
+move 1 from 1 to 9
+move 5 from 9 to 5
+move 4 from 3 to 2
+move 1 from 4 to 2
+move 1 from 3 to 8
+move 3 from 8 to 2
+move 19 from 8 to 7
+move 6 from 7 to 6
+move 4 from 5 to 2
+move 9 from 7 to 5
+move 1 from 7 to 1
+move 5 from 6 to 9
+move 1 from 7 to 4
+move 1 from 6 to 7
+move 1 from 4 to 7
+move 1 from 1 to 2
+move 2 from 7 to 3
+move 6 from 5 to 9
+move 9 from 9 to 1
+move 17 from 5 to 4
+move 2 from 3 to 1
+move 13 from 4 to 7
+move 3 from 3 to 5
+move 7 from 1 to 4
+move 1 from 5 to 8
+move 2 from 5 to 2
+move 6 from 7 to 3
+move 1 from 5 to 7
+move 1 from 9 to 1
+move 2 from 3 to 2
+move 1 from 9 to 3
+move 9 from 7 to 3
+move 10 from 3 to 5
+move 8 from 4 to 2
+move 1 from 4 to 1
+move 13 from 2 to 4
+move 5 from 4 to 3
+move 1 from 5 to 9
+move 1 from 7 to 2
+move 6 from 4 to 2
+move 4 from 1 to 8
+move 3 from 4 to 6
+move 9 from 8 to 9
+move 17 from 2 to 3
+move 2 from 8 to 6
+move 1 from 4 to 3
+move 2 from 6 to 3
+move 2 from 1 to 3
+move 13 from 3 to 4
+move 8 from 9 to 8
+move 7 from 4 to 6
+move 3 from 5 to 6
+move 5 from 8 to 2
+move 9 from 6 to 1
+move 7 from 2 to 4
+move 2 from 6 to 9
+move 1 from 1 to 5
+move 18 from 3 to 8
+move 5 from 1 to 3
+move 1 from 6 to 1
+move 9 from 4 to 7
+move 11 from 8 to 7
+move 5 from 7 to 5
+move 2 from 4 to 5
+move 1 from 6 to 2
+move 13 from 7 to 8
+move 1 from 4 to 9
+move 1 from 9 to 6
+move 4 from 1 to 5
+move 1 from 7 to 6
+move 9 from 5 to 7
+move 8 from 5 to 6
+move 10 from 7 to 2
+move 1 from 5 to 7
+move 1 from 7 to 1
+move 17 from 8 to 2
+move 9 from 6 to 7
+move 6 from 7 to 1
+move 2 from 7 to 2
+move 1 from 4 to 2
+move 12 from 2 to 8
+move 7 from 1 to 2
+move 6 from 8 to 6
+move 3 from 8 to 2
+move 1 from 7 to 2
+move 2 from 3 to 4
+move 1 from 4 to 9
+move 2 from 3 to 5
+move 2 from 3 to 7
+move 1 from 4 to 6
+move 2 from 7 to 1
+move 7 from 2 to 7
+move 6 from 7 to 1
+move 1 from 5 to 2
+move 6 from 8 to 4
+move 4 from 9 to 7
+move 1 from 5 to 2
+move 3 from 8 to 1
+move 1 from 9 to 4
+move 1 from 7 to 8
+move 1 from 8 to 1
+move 4 from 7 to 8
+move 1 from 4 to 2
+move 3 from 6 to 9
+move 2 from 9 to 7
+move 1 from 9 to 3
+move 2 from 4 to 3
+move 2 from 8 to 3
+move 5 from 3 to 4
+move 4 from 6 to 2
+move 8 from 2 to 9
+move 1 from 6 to 5
+move 10 from 2 to 3
+move 2 from 8 to 3
+move 8 from 9 to 3
+move 9 from 2 to 5
+move 1 from 2 to 4
+move 1 from 2 to 3
+move 7 from 5 to 6
+move 1 from 5 to 7
+move 13 from 3 to 4
+move 2 from 7 to 8
+move 5 from 3 to 1
+move 1 from 5 to 3
+move 1 from 8 to 5
+move 1 from 2 to 8
+move 1 from 7 to 9
+move 1 from 4 to 2
+move 15 from 4 to 8
+move 6 from 4 to 7
+move 6 from 7 to 8
+move 1 from 6 to 5
+move 1 from 4 to 6
+move 1 from 9 to 6
+move 2 from 5 to 2
+move 6 from 6 to 4
+move 6 from 1 to 8
+move 6 from 4 to 9
+move 2 from 6 to 1
+move 1 from 2 to 9
+move 26 from 8 to 1
+move 4 from 3 to 7
+move 2 from 2 to 5
+move 16 from 1 to 4
+move 3 from 9 to 8
+move 3 from 8 to 7
+move 3 from 5 to 1
+move 2 from 9 to 2
+move 1 from 9 to 7
+move 1 from 9 to 1
+move 8 from 4 to 1
+move 4 from 4 to 9
+move 1 from 2 to 3
+move 1 from 3 to 7
+move 2 from 8 to 2
+move 3 from 4 to 2
+move 1 from 4 to 7
+move 9 from 7 to 5
+move 1 from 9 to 8
+move 2 from 9 to 8
+move 5 from 5 to 7
+move 1 from 9 to 5
+move 6 from 2 to 6
+move 1 from 8 to 2
+move 5 from 6 to 5
+move 1 from 7 to 4
+move 3 from 8 to 9
+move 3 from 9 to 7
+move 1 from 6 to 4
+move 2 from 4 to 1
+move 2 from 5 to 8
+move 1 from 2 to 9
+move 2 from 8 to 9
+move 3 from 9 to 3
+move 8 from 7 to 3
+move 4 from 5 to 8
+move 1 from 3 to 9
+move 3 from 5 to 8
+move 1 from 5 to 3
+move 6 from 8 to 6
+move 3 from 3 to 9
+move 5 from 3 to 2
+move 5 from 6 to 4
+move 14 from 1 to 5
+move 8 from 5 to 6
+move 2 from 3 to 2
+move 4 from 9 to 1
+move 1 from 8 to 7
+move 7 from 2 to 3
+move 6 from 3 to 7
+move 3 from 5 to 3
+move 1 from 3 to 9
+move 12 from 1 to 5
+move 1 from 9 to 7
+move 2 from 3 to 1
+move 1 from 7 to 8
+move 1 from 8 to 7
+move 2 from 3 to 6
+move 2 from 1 to 9
+move 2 from 5 to 6
+move 2 from 9 to 7
+move 9 from 7 to 3
+move 7 from 1 to 5
+move 5 from 5 to 2
+move 8 from 6 to 8
+move 5 from 8 to 9
+

2022/05-supply-stacks/second.zig

@@ -0,0 +1,61 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    var output = try solve(example, allocator);
+    try std.testing.expect(std.mem.eql(u8, output, "MCD"));
+
+    const result = try solve(input, allocator);
+    try std.io.getStdOut().writer().print("{s}\n", .{result});
+}
+
+fn solve(puzzle: []const u8, allocator: std.mem.Allocator) ![]u8 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var line = it.next() orelse unreachable;
+    // Initializations from the first line
+    const size = (line.len + 1) / 4;
+    var output = try allocator.alloc(u8, size);
+    var stacks = try allocator.alloc(std.ArrayList(u8), size);
+    for (stacks) |*stack| {
+        stack.* = std.ArrayList(u8).init(allocator);
+    }
+    // parse stacks
+    while (true) {
+        var i: usize = 0;
+        while (i < size) : (i += 1) {
+            const v = line[i * 4 + 1];
+            if (v != ' ') {
+                try stacks[i].insert(0, v);
+            }
+        }
+        line = it.next() orelse unreachable;
+        if (line[0] != '[') { // we got the line with numbers
+            break;
+        }
+    }
+    // process rules
+    while (it.next()) |l| {
+        var elts = std.mem.split(u8, l, " ");
+        _ = elts.next() orelse unreachable; // the move word
+        var n = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10);
+        _ = elts.next() orelse unreachable; // the from word
+        const s = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10) - 1;
+        _ = elts.next() orelse unreachable; // the to word
+        const d = try std.fmt.parseInt(u8, elts.next() orelse unreachable, 10) - 1;
+        const nl = stacks[s].items.len - n;
+        try stacks[d].appendSlice(stacks[s].items[nl..]);
+        stacks[s].items.len = nl;
+    }
+    // generate output
+    var i: usize = 0;
+    while (i < size) : (i += 1) {
+        output[i] = stacks[i].pop();
+    }
+    return output;
+}