49 lines
1.4 KiB
Zig
49 lines
1.4 KiB
Zig
const std = @import("std");
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pub const title = "Day 03: Lobby";
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pub fn run(_: std.mem.Allocator) !void {
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const input = @embedFile("./input/day03.txt");
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var lines = std.mem.tokenizeScalar(u8, input, '\n');
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var accumulator: u32 = 0;
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while (lines.next()) |line| {
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var first_digit: u8 = 0;
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var first_digit_index: usize = 0;
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for (line[0..line.len - 1], 0..) |c, i| {
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const digit = try std.fmt.charToDigit(c, 10);
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if (digit > first_digit) {
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first_digit = digit;
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first_digit_index = i;
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}
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}
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std.debug.print("first = {d}\n", .{first_digit});
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var second_digit: u8 = 0;
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if (first_digit_index == line.len - 2) {
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const c = line[line.len - 1];
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second_digit = try std.fmt.charToDigit(c, 10);
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} else {
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for (line[first_digit_index + 1..]) |c| {
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const digit = try std.fmt.charToDigit(c, 10);
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if (digit > second_digit) {
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second_digit = digit;
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}
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}
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}
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std.debug.print("second = {d}\n", .{second_digit});
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const joltage = first_digit * 10 + second_digit;
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accumulator += joltage;
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}
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var buffer: [8]u8 = undefined;
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var stdout_writer = std.fs.File.stdout().writer(&buffer);
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const stdout = &stdout_writer.interface;
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try stdout.print("{d}\n", .{accumulator});
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try stdout.flush();
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}
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