2022-02 in zig

2022/02-rock-paper-scissors/example

@@ -0,0 +1,3 @@
+A Y
+B X
+C Z

2022/02-rock-paper-scissors/first.zig

@@ -0,0 +1,25 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    try std.testing.expectEqual(solve(example), 15);
+    const result = try solve(input);
+    try std.io.getStdOut().writer().print("{}\n", .{result});
+}
+
+const scores = [3][3]u8{ // X  Y  Z
+    [3]u8{ 4, 8, 3 }, // A  4  8  3
+    [3]u8{ 1, 5, 9 }, // B  1  5  9
+    [3]u8{ 7, 2, 6 }, // C  7  2  6
+};
+
+fn solve(puzzle: []const u8) !u64 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var tot: u64 = 0;
+    while (it.next()) |line| {
+        tot += scores[line[0] - 'A'][line[2] - 'X'];
+    }
+    return tot;
+}

2022/02-rock-paper-scissors/second.zig

@@ -0,0 +1,32 @@
+const std = @import("std");
+
+const example = @embedFile("example");
+const input = @embedFile("input");
+
+pub fn main() anyerror!void {
+    try std.testing.expectEqual(solve(example), 12);
+    const result = try solve(input);
+    try std.io.getStdOut().writer().print("{}\n", .{result});
+}
+
+const scores = [3][3]u8{ // X  Y  Z
+    [3]u8{ 4, 8, 3 }, // A  4  8  3
+    [3]u8{ 1, 5, 9 }, // B  1  5  9
+    [3]u8{ 7, 2, 6 }, // C  7  2  6
+};
+
+const strategy = [3][3]u8{ // X  Y  Z
+    [3]u8{ 2, 0, 1 }, //   A  2  0  1
+    [3]u8{ 0, 1, 2 }, //   B  0  1  2
+    [3]u8{ 1, 2, 0 }, //   C  1  2  0
+};
+
+fn solve(puzzle: []const u8) !u64 {
+    var it = std.mem.tokenize(u8, puzzle, "\n");
+    var tot: u64 = 0;
+    while (it.next()) |line| {
+        const move = strategy[line[0] - 'A'][line[2] - 'X'];
+        tot += scores[line[0] - 'A'][move];
+    }
+    return tot;
+}