Saves again

Author: romellem

docs/2019/day/16.md

@@ -1,41 +1,68 @@
+```js
+const fillPattern = (function () {
+	let cachedPatterns = {};
+	return (n) => {
+		if (cachedPatterns[n]) {
+			return cachedPatterns[n];
+		}
+
+		let pattern = [];
+		for (let num of [0, 1, 0, -1]) {
+			for (let i = 0; i < n; i++) {
+				pattern.push(num);
+			}
+		}
+
+		// Offset the whole pattern left by one
+		let first_digit = pattern.shift();
+		pattern.push(first_digit);
+
+		cachedPatterns[n] = pattern;
+
+		return pattern;
+	};
+})();
+
+var table = function (input) {
+	let pad = String(input.length).length;
+	let space = '#'.padStart(pad);
+	let header = `| ${space} |   ${input.join('  |   ')}  |`;
+	let line = header
+		.split('')
+		.map((c) => (c === '|' ? '|' : '-'))
+		.join('');
+	let grid = [];
+
+	let mid = Math.floor(input.length / 2);
+	for (let y = 0; y < input.length; y++) {
+		let row = [];
+		let pattern = fillPattern(y + 1);
+		for (let x = 0; x < input.length; x++) {
+			let char = '    ';
+			let i = x % pattern.length;
+			let scalar = pattern[i];
+
+			if (y >= mid) {
+				if (scalar === 1) {
+					char = ` *${input[x]}*`;
+				} else if (scalar === -1) {
+					char = `*-${input[x]}*`;
+				}
+			} else {
+				if (scalar === 1) {
+					char = `  ${input[x]} `;
+				} else if (scalar === -1) {
+					char = ` -${input[x]} `;
+				}
+			}
+
+			row.push(char);
+		}
+
+		grid.push(`| ${(y + 1).toString().padStart(pad)} | ${row.join(' | ')} |`);
+	}
+
+	let output = [header, line, ...grid].join('\n');
+	return output;
+};
 ```
-var table = function(input) {
-  let pad = String(input.length).length;
-  let space = '#'.padStart(pad);
-  let header = `| ${space} |   ${input.join('  |   ')}  |`;
-  let line = header.split('').map(c => c === '|' ? '|' : '-').join('');
-  let grid = [];
-
-  let mid = Math.floor(input.length / 2);
-  for (let y = 0; y < input.length; y++) {
-    let row = [];
-    let pattern = fillPattern(y + 1);
-    for (let x = 0; x < input.length; x++) {
-      let char = '    ';
-      let i = x % pattern.length;
-      let scalar = pattern[i];
-
-      if (y >= mid) {
-        if (scalar === 1) {
-          char = ` *${input[x]}*`;
-        } else if (scalar === -1) {
-          char = `*-${input[x]}*`;
-        }
-      } else {
-        if (scalar === 1) {
-          char = `  ${input[x]} `;
-        } else if (scalar === -1) {
-          char = ` -${input[x]} `;
-        }
-      }
-
-      row.push(char);
-    }
-
-    grid.push(`| ${(y+1).toString().padStart(pad)} | ${row.join(' | ')} |`);
-  }
-
-  let output = [header, line, ...grid].join('\n');
-  return output;
-}
-```