36 lines
933 B
Zig
36 lines
933 B
Zig
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const std = @import("std");
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const example = @embedFile("example");
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const input = @embedFile("input");
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pub fn main() anyerror!void {
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const result = try solve(input);
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try std.io.getStdOut().writer().print("{}\n", .{result});
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}
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fn solve(puzzle: []const u8) !u64 {
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var it = std.mem.tokenize(u8, puzzle, "\n");
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var aim: u64 = 0;
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var pos: u64 = 0;
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var depth: u64 = 0;
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while (it.next()) |line| {
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var it2 = std.mem.tokenize(u8, line, " ");
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const step = it2.next() orelse unreachable;
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const n: u64 = std.fmt.parseInt(u64, it2.next().?, 10) catch unreachable;
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switch (step[0]) {
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'f' => {
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pos += n;
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depth += n * aim;
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},
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'd' => aim += n,
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'u' => aim -= n,
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else => unreachable,
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}
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}
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return pos * depth;
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}
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test "solve" {
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try std.testing.expectEqual(solve(example), 900);
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}
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