AoC day 4

AdventOfCode2018/4thDay/challenge1/index.js

@@ -0,0 +1,71 @@
+class Guard {
+    constructor (id) {
+        this.id = id;
+        this.minutesAsleep = Array.from({ length: 60 }).map(() => 0);
+        this.fellAsleepAt = null;
+    }
+  
+    sleep (fellAsleepAt) {
+        this.fellAsleepAt = fellAsleepAt;
+    }
+  
+    awake (awokeAt) {
+        for (let i = this.fellAsleepAt; i < awokeAt; i++) {
+            this.minutesAsleep[i] += 1;
+        }
+    }
+  
+    get totalSleepMinutes () {
+        return this.minutesAsleep.reduce((a, b) => a + b, 0);
+    }
+  
+    get sleepiestMinute () {
+        return this.minutesAsleep
+            .map((value, index) => ({ index, value }))
+            .sort((a, b) => b.value - a.value)[0].index;
+    }
+}
+
+const sleep = (input) => {
+    const guards = {};
+    const schedule = input
+        .split('\n')
+        .map((x) => x.trim())
+        .sort()
+        .map((x) => {
+            const parts = x.match(/\[(\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2})\] (.*)/);
+
+        return {
+            minute: +parts[5],
+            message: parts[6],
+        };
+    });
+
+    let currentGuard = null;
+
+    for (let i = 0; i < schedule.length; i++) {
+        const { message, minute } = schedule[i];
+
+        if (/Guard/.test(message)) {
+            const parts = message.match(/Guard #(\d+) begins shift/);
+            const guardId = +parts[1];
+            const guard = guards[guardId] ? guards[guardId] : new Guard(guardId);
+
+            currentGuard = guards[guardId] = guard;
+        } else if (message === 'falls asleep') {
+            currentGuard.sleep(minute);
+        } else if (message === 'wakes up') {
+            currentGuard.awake(minute);
+        }
+    }
+    const sleepiestGuard = Object
+        .keys(guards)
+        .map((guardId) => guards[guardId])
+        .sort((a, b) => b.totalSleepMinutes - a.totalSleepMinutes)[0];
+    
+        return sleepiestGuard.id * sleepiestGuard.sleepiestMinute;
+}
+
+const fs = require('fs');
+console.log(sleep(fs.readFileSync("input.txt").toString()));
+