2018 day 12 complete

2018/12/input.txt

@@ -0,0 +1,34 @@
+initial state: ##....#.#.#...#.#..#.#####.#.#.##.#.#.#######...#.##....#..##....#.#..##.####.#..........#..#...#
+
+..#.# => #
+.#### => #
+#.... => .
+####. => #
+...## => .
+.#.#. => .
+..#.. => .
+##.#. => .
+#.#.# => #
+..... => .
+#.#.. => .
+....# => .
+.#..# => .
+###.# => #
+#..#. => .
+##### => .
+...#. => #
+#.##. => #
+.#.## => #
+#..## => #
+.##.. => #
+##.## => .
+..### => .
+###.. => .
+##..# => #
+.#... => #
+.###. => #
+#.### => .
+.##.# => .
+#...# => #
+##... => .
+..##. => .

2018/12/part1.js

@@ -0,0 +1,56 @@
+const fs = require('fs'); // file system
+const input = fs.readFileSync(`${__dirname}/input.txt`, 'utf-8')	// read the input file
+	.split('\n');	// split on lines
+
+// get the initial state from the input
+let state = input[0].slice('initial state: '.length);
+
+let rules = {};
+
+// extract all rules from input
+for (const line of input.splice(2)) {
+	rules[line.slice(0, 5)] = line.slice(9);
+}
+
+// to add extra pots as if there were endless pots
+function expand () {
+	state = state.replace(/^(\.+)?/, '.....');
+	state = state.replace(/(\.+)?$/, '.....');
+}
+
+let zero = 5;
+// add empty pots
+expand();
+console.log(Array(20-zero).join(' ')+state);
+
+for (let i = 0; i < 20; i++){
+
+	// create 'empty' array of '.'s
+	const pots = Array(3).join('.').split('');
+
+	state.split('').forEach((_, n) => {
+		// get the section to look at of prev gen
+		const sect = state.slice(n-2, n+3);
+		if (sect.length !== 5) { return }
+
+		// get the value of the matching rule
+		let plant = rules[sect];
+		if (!plant) { return }
+
+		// replace the value in the next gen
+		pots.push(plant);
+	});
+	// move the '0th pot' marker
+	zero -= pots.indexOf('#') - 5;
+	state = pots.join('');
+
+	// add empty pots
+	expand();
+	console.log(Array(20-zero).join(' ')+state);
+}
+
+const result = state.split('').reduce((val, pot, index) => {
+	return (Number(val) || 0) + (pot === '#' ? index - zero : 0);
+})
+
+console.log(result);

2018/12/part2.js

@@ -0,0 +1,70 @@
+const fs = require('fs'); // file system
+const input = fs.readFileSync(`${__dirname}/input.txt`, 'utf-8')	// read the input file
+	.split('\n');	// split on lines
+
+// get the initial state from the input
+let state = input[0].slice('initial state: '.length);
+
+let rules = {};
+
+// extract all rules from input
+for (const line of input.splice(2)) {
+	rules[line.slice(0, 5)] = line.slice(9);
+}
+
+// to add extra pots as if there were endless pots
+function expand (s) {
+	let r = s.replace(/^(\.+)?/, '.....');
+	r = r.replace(/(\.+)?$/, '.....');
+	return r;
+}
+
+let zero = 5;
+// add empty pots
+state = expand(state);
+
+let done = false;
+for (var i = 0; i < 250; i++){
+
+
+	if (done) {
+		var gen = i;
+		break;
+	}
+
+	// create 'empty' array of '.'s
+	const pots = Array(3).join('.').split('');
+
+	state.split('').forEach((_, n) => {
+		// get the section to look at of prev gen
+		const sect = state.slice(n-2, n+3);
+		if (sect.length !== 5) { return }
+
+		// get the value of the matching rule
+		let plant = rules[sect];
+		if (!plant) { return }
+
+		// replace the value in the next gen
+		pots.push(plant);
+	});
+	// move the '0th pot' marker
+	zero -= pots.indexOf('#') - 5;
+
+	// if the pattern is repeating. process is done.
+	done = expand(pots.join('')) === state;
+
+	// store the generation with extra pots.
+	state = expand(pots.join(''));
+
+
+	// console.log(Array(20-zero).join(' ')+state);	// output with pot 0 aligned
+	// console.log(state);	// output misaligned
+
+}
+
+// calculate the value of last gen
+const result = state.split('').reduce((val, pot, index) => {
+	return (Number(val) || 0) + (pot === '#' ? index - zero : 0);
+})
+
+console.log(result + (50000000000 - gen) * state.match(/#/g).length)

2018/12/test.txt

@@ -0,0 +1,16 @@
+initial state: #..#.#..##......###...###
+
+...## => #
+..#.. => #
+.#... => #
+.#.#. => #
+.#.## => #
+.##.. => #
+.#### => #
+#.#.# => #
+#.### => #
+##.#. => #
+##.## => #
+###.. => #
+###.# => #
+####. => #

2018/README.md

@@ -1,34 +1,37 @@
 # [2018](https://adventofcode.com/2018 "2018 puzzle calendar")
-1. [:star: :star:](https://adventofcode.com/2015/day/1 "see puzzle")
+1	|	[:star: :star:](https://adventofcode.com/2015/day/1 "see puzzle")
-2. [:star: :star:](https://adventofcode.com/2015/day/2 "see puzzle")
+--: | :--
-3. [:star: :star:](https://adventofcode.com/2015/day/3 "see puzzle")
+2	|	[:star: :star:](https://adventofcode.com/2015/day/2 "see puzzle")
-4. [:star: :star:](https://adventofcode.com/2015/day/4 "see puzzle")
+3	|	[:star: :star:](https://adventofcode.com/2015/day/3 "see puzzle")
-5. [:star: :star:](https://adventofcode.com/2015/day/5 "see puzzle")
+4	|	[:star: :star:](https://adventofcode.com/2015/day/4 "see puzzle")
-6. [:star: :star:](https://adventofcode.com/2015/day/6 "see puzzle")
+5	|	[:star: :star:](https://adventofcode.com/2015/day/5 "see puzzle")
-7. [:star: :star:](https://adventofcode.com/2015/day/7 "see puzzle")
+6	|	[:star: :star:](https://adventofcode.com/2015/day/6 "see puzzle")
-8. [:star: :star:](https://adventofcode.com/2015/day/8 "see puzzle")
+7	|	[:star: :star:](https://adventofcode.com/2015/day/7 "see puzzle")
-9. [:star: :star:](https://adventofcode.com/2015/day/9 "see puzzle")
+8	|	[:star: :star:](https://adventofcode.com/2015/day/8 "see puzzle")
-10. [:star: :star:](https://adventofcode.com/2015/day/9 "see puzzle")
+9	|	[:star: :star:](https://adventofcode.com/2015/day/9 "see puzzle")
-11. [:star: :star:](https://adventofcode.com/2015/day/10 "see puzzle")
+10	|	[:star: :star:](https://adventofcode.com/2015/day/10 "see puzzle")
+11	|	[:star: :star:](https://adventofcode.com/2015/day/11 "see puzzle")
+12	|	[:star: :star:](https://adventofcode.com/2015/day/12 "see puzzle")
 
 # Languages Used
 ### Python
-2. :star: :star:
+2	|	:star: :star:
-
+--: | :--
-
+11	|	:star: :star:
-11. :star: :star:
 
 ### Node JS
-1. :star: :star:
 
-
+1	|	:star: :star:
-3. :star: :star:
+--: | :--
-4. :star: :star:
+3	|	:star: :star:
-5. :star: :star:
+4	|	:star: :star:
-6. :star: :star:
+5	|	:star: :star:
-7. :star: :star:
+6	|	:star: :star:
-8. :star: :star:
+7	|	:star: :star:
-9. :star: :star:
+8	|	:star: :star:
+9 	|	:star: :star:
+12	|	:star: :star:
 
 ### Java (Processing)
-10. :star: :star:
+1	|	:star: :star:
+--: | :--

README.md

@@ -1,6 +1,6 @@
 # Advent of Code Solutions
 
-It's a fun challenge. [2018](#2018) is currently in progress.
+It's a fun challenge! You should check it out if you like coding and are interested in algorithms.
 
 ```js
 if (advent) {
@@ -11,24 +11,25 @@ if (advent) {
 # Completed Challenges
 #### [2015](https://adventofcode.com/2015 "2015 puzzle calendar")
 1. [:star: :star:](https://adventofcode.com/2015/day/1 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2015/day/2 "see puzzle")
+2. [:star: :star:](https://adventofcode.com/2015/day/2 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2015/day/3 "see puzzle")
+3. [:star: :star:](https://adventofcode.com/2015/day/3 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2015/day/4 "see puzzle")
+4. [:star: :star:](https://adventofcode.com/2015/day/4 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2015/day/5 "see puzzle")
+5. [:star: :star:](https://adventofcode.com/2015/day/5 "see puzzle")
-1. [:star:](https://adventofcode.com/2015/day/6 "see puzzle")
+6. [:star:](https://adventofcode.com/2015/day/6 "see puzzle")
 
 #### [2018](https://adventofcode.com/2018 "2018 puzzle calendar")
 1. [:star: :star:](https://adventofcode.com/2018/day/1 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/2 "see puzzle")
+2. [:star: :star:](https://adventofcode.com/2018/day/2 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/3 "see puzzle")
+3. [:star: :star:](https://adventofcode.com/2018/day/3 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/4 "see puzzle")
+4. [:star: :star:](https://adventofcode.com/2018/day/4 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/5 "see puzzle")
+5. [:star: :star:](https://adventofcode.com/2018/day/5 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/6 "see puzzle")
+6. [:star: :star:](https://adventofcode.com/2018/day/6 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/7 "see puzzle")
+7. [:star: :star:](https://adventofcode.com/2018/day/7 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/8 "see puzzle")
+8. [:star: :star:](https://adventofcode.com/2018/day/8 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/9 "see puzzle")
+9. [:star: :star:](https://adventofcode.com/2018/day/9 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/10 "see puzzle")
+10. [:star: :star:](https://adventofcode.com/2018/day/10 "see puzzle")
-1. [:star: :star:](https://adventofcode.com/2018/day/11 "see puzzle")
+11. [:star: :star:](https://adventofcode.com/2018/day/11 "see puzzle")
+12. [:star: :star:](https://adventofcode.com/2018/day/12 "see puzzle")
 
 ## Languages Used
 * Python