Add solution #1604

Author: JoshCrozier

README.md

@@ -1,4 +1,4 @@
-# 1,413 LeetCode solutions in JavaScript
+# 1,414 LeetCode solutions in JavaScript
 
 [https://leetcodejavascript.com](https://leetcodejavascript.com)
 
@@ -1238,6 +1238,7 @@
 1600|[Throne Inheritance](./solutions/1600-throne-inheritance.js)|Medium|
 1601|[Maximum Number of Achievable Transfer Requests](./solutions/1601-maximum-number-of-achievable-transfer-requests.js)|Hard|
 1603|[Design Parking System](./solutions/1603-design-parking-system.js)|Easy|
+1604|[Alert Using Same Key-Card Three or More Times in a One Hour Period](./solutions/1604-alert-using-same-key-card-three-or-more-times-in-a-one-hour-period.js)|Medium|
 1657|[Determine if Two Strings Are Close](./solutions/1657-determine-if-two-strings-are-close.js)|Medium|
 1668|[Maximum Repeating Substring](./solutions/1668-maximum-repeating-substring.js)|Easy|
 1669|[Merge In Between Linked Lists](./solutions/1669-merge-in-between-linked-lists.js)|Medium|

solutions/1604-alert-using-same-key-card-three-or-more-times-in-a-one-hour-period.js

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+/**
+ * 1604. Alert Using Same Key-Card Three or More Times in a One Hour Period
+ * https://leetcode.com/problems/alert-using-same-key-card-three-or-more-times-in-a-one-hour-period/
+ * Difficulty: Medium
+ *
+ * LeetCode company workers use key-cards to unlock office doors. Each time a worker uses their
+ * key-card, the security system saves the worker's name and the time when it was used. The system
+ * emits an alert if any worker uses the key-card three or more times in a one-hour period.
+ *
+ * You are given a list of strings keyName and keyTime where [keyName[i], keyTime[i]] corresponds
+ * to a person's name and the time when their key-card was used in a single day.
+ *
+ * Access times are given in the 24-hour time format "HH:MM", such as "23:51" and "09:49".
+ *
+ * Return a list of unique worker names who received an alert for frequent keycard use. Sort the
+ * names in ascending order alphabetically.
+ *
+ * Notice that "10:00" - "11:00" is considered to be within a one-hour period, while
+ * "22:51" - "23:52" is not considered to be within a one-hour period.
+ */
+
+/**
+ * @param {string[]} keyName
+ * @param {string[]} keyTime
+ * @return {string[]}
+ */
+var alertNames = function(keyName, keyTime) {
+  const usageMap = new Map();
+  for (let i = 0; i < keyName.length; i++) {
+    if (!usageMap.has(keyName[i])) {
+      usageMap.set(keyName[i], []);
+    }
+    usageMap.get(keyName[i]).push(timeToMinutes(keyTime[i]));
+  }
+
+  const result = [];
+  for (const [name, times] of usageMap) {
+    times.sort((a, b) => a - b);
+    for (let i = 2; i < times.length; i++) {
+      if (times[i] - times[i - 2] <= 60) {
+        result.push(name);
+        break;
+      }
+    }
+  }
+
+  return result.sort();
+
+  function timeToMinutes(time) {
+    const [hours, minutes] = time.split(':').map(Number);
+    return hours * 60 + minutes;
+  }
+};