Cleaned up my solution more.

This commit is contained in:
Andrew Lalis 2023-12-01 10:21:40 -05:00
parent fc6d6a3e49
commit 6fa33b4e3e
2 changed files with 25 additions and 31 deletions

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@ -3,3 +3,5 @@
This repository has my solutions for this year's Advent of Code challenges. Each day's challenge will be placed into a directory named `day_N`, where `N` is the day of the challenge. Each day will have a solution program named `solution.*` (with the filetype depending on which programming language I used).
For D programs, you can simply run them with `rdmd solution.d`.
Note that I try and solve the problems as fast as possible, but then I go back and clean up my solution, so what you see isn't really my ugly first attempt.

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@ -5,21 +5,27 @@ import std.string : splitLines;
import std.algorithm;
import std.stdio;
import std.uni : isNumber;
import std.functional;
void part1() {
readText("part_1_input.txt")
.splitLines()
.map!((line) {
/// Parses the first and last digits, using a function F to determine if and
/// what digit is at a string at a particular index. F should return -1 if no
/// digit exists.
int parseDigits(int delegate(string, size_t) F)(string s) {
int a = -1, b = -1;
for (size_t i = 0; i < line.length; i++) {
if (a == -1 && isNumber(line[i])) a = line[i] - '0';
if (b == -1 && isNumber(line[$-i-1])) b = line[$-i-1] - '0';
for (size_t i = 0; i < s.length; i++) {
int an = F(s, i);
int bn = F(s, s.length-i-1);
if (a == -1 && an != -1) a = an;
if (b == -1 && bn != -1) b = bn;
if (a != -1 && b != -1) break;
}
return a * 10 + b;
})
.sum()
.writeln();
}
void part1() {
readText("part_1_input.txt").splitLines()
.map!(line => parseDigits!((s, i) => isNumber(s[i]) ? s[i] - '0' : -1)(line))
.sum().writeln();
}
void part2() {
@ -27,28 +33,14 @@ void part2() {
if (isNumber(s[idx])) return s[idx] - '0';
const string[] words = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"];
static foreach (size_t i, string word; words) {
if (s.length - idx >= word.length && s[idx .. idx + word.length] == word) {
return cast(int) i + 1;
}
if (s.length - idx >= word.length && s[idx .. idx + word.length] == word) return cast(int) i + 1;
}
return -1;
}
readText("part_2_input.txt")
.splitLines()
.map!((line) {
int a = -1, b = -1;
for (size_t i = 0; i < line.length; i++) {
int an = findDigit(line, i);
int bn = findDigit(line, line.length-i-1);
if (a == -1 && an != -1) a = an;
if (b == -1 && bn != -1) b = bn;
if (a != -1 && b != -1) break;
}
return a * 10 + b;
})
.sum()
.writeln();
readText("part_2_input.txt").splitLines()
.map!(line => parseDigits!((s, i) => findDigit(s, i))(line))
.sum().writeln();
}
void main() {