BOJ 5015 데추주 제너레이터

boj_5015_gen.js

const {mt_rand, shuffle} = require("./utils");

module.exports = () => {
	let ret = ``;
	let sz = mt_rand(1, 100);
	while (sz--) {
		let c = mt_rand(0, 50);
		if (c >= 27) ret += "*";
		else if (c === 26) ret += ".";
		else ret += `${String.fromCharCode("a".charCodeAt(0) + c)}`;
	}
	let pattern = ret;
	let n = 100;
	ret += `\n${n}\n`;
	while (n--) {
                let nxt = "";
                for (let c of pattern) {
                        if (c !== "*") nxt += c;
                        else if (mt_rand(0, 1)) nxt += `${String.fromCharCode("a".charCodeAt(0) + mt_rand(0, 25))}`;
                }
		if (nxt.length === 0) nxt = `${String.fromCharCode("a".charCodeAt(0) + mt_rand(0, 25))}`;
		if (mt_rand(0, 1)) {
			ret += `${nxt}\n`;
		} else {
			let pos = mt_rand(0, nxt.length);
			if (nxt.length === 100) ret += `${nxt}\n`;
			else ret += `${nxt.substr(0, pos) + String.fromCharCode("a".charCodeAt(0) + mt_rand(0, 25)) + nxt.substr(pos)}\n`;
		}
	}
	return ret;
};