aoc/2023/03/part1.ts

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2023-12-03 21:00:47 +00:00
enum LogLevel {
Answer,
Info,
Debug,
}
const LOG_LEVEL = LogLevel.Info;
const print = (level: keyof typeof LogLevel, msg: string) => {
if (LogLevel[level] <= LOG_LEVEL) {
console.log(level+': '+msg);
}
}
const file = Bun.file("input.txt");
const input = await file.text();
function* findNumbers (schematic: string[]) {
const matcher = /[0-9]+/g;
for (const i in schematic) {
const line = schematic[i];
for (let res = matcher.exec(line); res !== null; res = matcher.exec(line)) {
const start = matcher.lastIndex - res[0].length;
const end = matcher.lastIndex - 1;
print('Debug',`"${res[0]}" at [${start}-${end}]`);
yield {
line: Number(i),
index: start,
len: res[0].length,
num: Number(res[0])
};
}
}
}
interface Match {
line: number,
index: number,
len: number,
num: number,
}
function isPartNumber (schematic: string[], match: Match): boolean {
const width = schematic[0].length - 1;
const height = schematic.length - 1;
let surroundings = "";
const start = Math.max(match.index-1, 0);
const end = Math.min(match.index + match.len, width);
if (match.line > 0) {
surroundings += schematic[match.line - 1].slice(start, end + 1) + " ";
}
if (match.index > 0) {
surroundings += schematic[match.line][start] + " ";
}
if (match.index + match.len + 1 < width) {
surroundings += schematic[match.line][end] + " ";
}
if (match.line < height) {
surroundings += schematic[match.line + 1].slice(start, end + 1) + " ";
}
print('Debug', `surroundings: ${surroundings}`)
return /[^0-9. ]/g.test(surroundings);
}
function main(): void {
const lines = input.trim().split("\n");
for (const line of lines) {
print('Info', line);
}
const partNumbers = [];
for (const match of findNumbers(lines)) {
if (isPartNumber(lines,match)) {
partNumbers.push(match.num);
}
}
print('Debug', `Part Numbers: ${partNumbers}`)
print('Answer', `${partNumbers.reduce((a,b)=>a+b)}`)
}
main();