use fmt;
use io;
use math;
use os;
use strconv;
use strings;

fn digits(num: u64) u64 = {
	return math::ceilf64(math::log10f64(num: f64)): u64;
};

export fn main() void = {
	let handle = os::open("input.txt")!;
	defer io::close(handle)!;

	let buf = io::drain(handle) as []u8;
	defer free(buf);

	let input = strings::fromutf8_unsafe(buf);
	let range_strings = strings::split(input, ",")!;

	let answer: u64 = 0;

	for (let i: size = 0; i < len(range_strings); i += 1) {
		let range_ends = strings::cut(strings::rtrim(range_strings[i], '\n'), "-");

		let start = strconv::stou64(range_ends.0)!;
		let end = strconv::stou64(range_ends.1)!;

		let start_digits = digits(start);
		let end_digits = digits(end);

		if (start_digits % 2 != 0 && end_digits % 2 != 0 && start_digits == end_digits) {
			continue;
		};

		for (let j = start; j <= end; j += 1) {
			let digits = digits(j);

			if (digits % 2 == 0) {
				let num_str = strconv::u64tos(j);

				let first_half = strings::sub(num_str, 0, len(num_str) / 2);
				let second_half = strings::sub(num_str, len(num_str) / 2, len(num_str));

				if (first_half == second_half) {
					answer += j;
				};
			};
		};
	};

	fmt::printfln("Answer: {}", answer)!;
};