Day 2

02/part1.js

@@ -0,0 +1,33 @@
+const fs = require('fs')
+const readline = require('readline');
+
+const readInterface = readline.createInterface({
+    input: fs.createReadStream('input'),
+    console: false
+});
+
+let re = /^(\d+)-(\d+) (\w+): (\w+)$/i
+let valid = 0;
+
+readInterface.on('line', function(line) {
+  let result = re.exec(line);
+  if (result == null) {
+    return;
+  }
+
+  let min = Number(result[1]);
+  let max = Number(result[2]);
+  let match = result[3];
+  let pass = result[4];
+
+  let count = 0;
+  pass.split('').forEach(x => x == match ? count++ : null);
+
+  if (count >= min && count <= max) {
+    valid++;
+  };
+});
+
+readInterface.on('close', function(line) {
+  console.log(valid);
+});

02/part2.js

@@ -0,0 +1,30 @@
+const fs = require('fs')
+const readline = require('readline');
+
+const readInterface = readline.createInterface({
+    input: fs.createReadStream('input'),
+    console: false
+});
+
+let re = /^(\d+)-(\d+) (\w+): (\w+)$/i
+let valid = 0;
+
+readInterface.on('line', function(line) {
+  let result = re.exec(line);
+  if (result == null) {
+    return;
+  }
+
+  let pos1 = Number(result[1]) - 1;
+  let pos2 = Number(result[2]) - 1;
+  let match = result[3];
+  let pass = result[4];
+
+  if ((pass[pos1] == match && pass[pos2] != match) || (pass[pos1] != match && pass[pos2] == match)) {
+    valid++;
+  };
+});
+
+readInterface.on('close', function(line) {
+  console.log(valid);
+});