usaco_util.ts

import axios from 'axios';
import { writeFileSync } from 'fs';
import { ProblemData } from './ProblemData';

const problems = require('./problems.json') as { [key: string]: ProblemData };
let report = 'added problems:\n```\n';

async function addProblem(id: number) {
  try {
    const url = `https://usaco.org/index.php?page=viewproblem2&cpid=${id}`;
    const response = await (await fetch(url)).text();
    const htmlContent: string = response;
    const problem = htmlContent.match(/<h2> Problem (\d). (.*) <\/h2>/)!;
    const number = problem[1],
      title = problem[2];
    const contest = htmlContent.match(
      /<h2> USACO (\d+) (December|January|February|(?:US Open)) Contest, (Bronze|Silver|Gold|Platinum) <\/h2>/
    )!;
    const year = contest[1],
      month = contest[2],
      division = contest[3];
    const sample_input =
      /<h4>SAMPLE INPUT:<\/h4>\s*<pre class='in'>\n?([\w\W]*?)<\/pre>/g;
    const sample_output =
      /<h4>SAMPLE OUTPUT:<\/h4>\s*<pre class='out'>\n?([\w\W]*?)<\/pre>/g;
    const inputs = [...htmlContent.matchAll(sample_input)!].map(
      match => match[1]
    );
    const outputs = [...htmlContent.matchAll(sample_output)!].map(
      match => match[1]
    );
    // console.log('Problem', number, title, year, month, division);
    problems[id] = {
      id: id,
      url,
      source: {
        sourceString: `${year} ${month} ${division}`,
        year: +year,
        contest: month,
        division: division,
      },
      submittable: true,
      title: {
        titleString: `${number}. ${title}`,
        place: +number,
        name: title,
      },
      input: 'stdin',
      output: 'stdout',
      samples: inputs.map((input, i) => ({
        input: input,
        output: outputs[i],
      })),
    };
    // console.log('Problem added!');
    console.log(
      `id ${id}: ${problems[id].title.name} (#${problems[id].title.place} from ${problems[id].source.sourceString})\n`
    );
    return true;
  } catch (error) {
    if (!(error instanceof TypeError)) console.log(error);
    return false;
  }
}

(async () => {
  // max id gap between two consecutive contests
  const MAX_GAP = 20;
  const LAST_ID = Math.max(...Object.keys(problems).map(Number));
  let last_added = LAST_ID;
  let id = last_added + 1;
  while (id - last_added < MAX_GAP) {
    if (await addProblem(id++)) {
      last_added = id - 1;
    }
  }
  if (last_added == LAST_ID) process.exit(0);
  report += '```';
  writeFileSync('problems.json', JSON.stringify(problems, null, 2));
})();