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const std = @import("std");
const Result = @import("util/aoc.zig").Result;
pub fn puzzle_1(input: []const u8) Result {
var iter = std.mem.split(u8, input, "\n");
var i: usize = 0;
mainLoop: while (iter.next()) |line| {
var buf = std.mem.zeroes([4]u32);
var buf_idx: usize = 0;
for (line) |c, idx| {
if (buf_idx > 3) buf_idx = 0;
buf[buf_idx] = @as(u32, 1) << @intCast(u5, c - 97); // 97 == 'a'
buf_idx += 1;
if (@popCount(buf[0] | buf[1] | buf[2] | buf[3]) == 4) {
i = idx + 1;
break :mainLoop;
}
}
}
return .{ .int = @intCast(i32, i) };
}
pub fn puzzle_2(input: []const u8) Result {
var iter = std.mem.split(u8, input, "\n");
var i: usize = 0;
mainLoop: while (iter.next()) |line| {
var buf = std.mem.zeroes([14]u32);
var buf_idx: usize = 0;
for (line) |c, idx| {
if (buf_idx > 13) buf_idx = 0;
buf[buf_idx] = @as(u32, 1) << @intCast(u5, c - 97); // 97 == 'a'
buf_idx += 1;
const hammer: u32 = blk: {
var hidx: usize = 0;
var tmp: u32 = 0;
while (hidx < 14) : (hidx += 1) tmp |= buf[hidx];
break :blk tmp;
};
if (@popCount(hammer) == 14) {
i = idx + 1;
break :mainLoop;
}
}
}
return .{ .int = @intCast(i32, i) };
}
//pub fn puzzle_2(input: []const u8) Result {
//var iter = std.mem.split(u8, input, "\n");
//var count: u16 = 0;
//mainLoop: while (true) {
//var parts = std.mem.zeroes([3]u64);
//for (parts) |*p| {
//const line = iter.next() orelse break :mainLoop;
//for (line) |_, i| {
//p.* |= @as(u64, 1) << @intCast(u6, line[i] - 65);
//}
//}
//count += char_to_priority(@intCast(u8, 65 + 63) - @clz(parts[0] & parts[1] & parts[2]));
//}
//return .{ .int = count };
//}
//fn char_to_priority(char: u8) u8 {
//if (char >= 65 and char <= 90)
//return char - 38;
//return char - 96;
//}
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