Solve 2020/06

2020/06/solution1.js

@@ -0,0 +1,23 @@
+const { readInput, sum } = require("./util");
+
+const { paragraphs } = readInput();
+
+function intersect(strA, strB) {
+  const setB = new Set(strB);
+  return strA
+    .split("")
+    .filter((el) => setB.has(el))
+    .join("");
+}
+function intersections(...strings) {
+  let res = strings[0];
+  for (const cur of strings.slice(1)) {
+    res = intersect(res, cur);
+  }
+  return res;
+}
+
+console.log("Part1:");
+console.log(sum(paragraphs.map((p) => new Set(p.replaceAll("\n", "")).size)));
+console.log("Part2:");
+console.log(sum(paragraphs.map((p) => intersections(...p.split("\n")).length)));

2020/06/util.js

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+const fs = require("fs");
+
+exports.readInput = function (filename = "input") {
+  const input = fs.readFileSync(filename, "utf-8").trim();
+  const lines = input.split("\n");
+  const paragraphs = input.split("\n\n");
+
+  let colLength = lines[0].length;
+  let colConsistentcy = true;
+  for (const line of lines) {
+    if (colLength != line.length) {
+      colConsistentcy = false;
+    }
+  }
+
+  const avgLength = sum(lines.map((l) => l.length)) / lines.length;
+
+  console.log("Number of lines:", lines.length);
+  console.log("Number of paragraphs", paragraphs.length);
+  console.log("Col-length is consistent:", colConsistentcy);
+  console.log("Average col-length", avgLength);
+
+  console.log("Sample:");
+  for (const line of lines.slice(0, 5)) {
+    console.log(line);
+  }
+  console.log("...");
+  for (const line of lines.slice(lines.length - 5, lines.length)) {
+    console.log(line);
+  }
+  console.log("=".repeat(process.stdout.columns));
+
+  return {
+    raw: input,
+    lines,
+    paragraphs,
+  };
+};
+
+const sum = (arr) => arr.reduce((a, b) => a + b, 0);
+exports.sum = sum;