> For the complete documentation index, see [llms.txt](https://jaywin.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jaywin.gitbook.io/leetcode/solutions/1604-alert-using-same-key-card-three-or-more-times-in-a-one-hour-period.md).

# 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>

## Description

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.

**Example 1:**

```
**Input:** keyName = ["daniel","daniel","daniel","luis","luis","luis","luis"], keyTime = ["10:00","10:40","11:00","09:00","11:00","13:00","15:00"]
**Output:** ["daniel"]
**Explanation:** "daniel" used the keycard 3 times in a one-hour period ("10:00","10:40", "11:00").
```

**Example 2:**

```
**Input:** keyName = ["alice","alice","alice","bob","bob","bob","bob"], keyTime = ["12:01","12:00","18:00","21:00","21:20","21:30","23:00"]
**Output:** ["bob"]
**Explanation:** "bob" used the keycard 3 times in a one-hour period ("21:00","21:20", "21:30").
```

**Example 3:**

```
**Input:** keyName = ["john","john","john"], keyTime = ["23:58","23:59","00:01"]
**Output:** []
```

**Example 4:**

```
**Input:** keyName = ["leslie","leslie","leslie","clare","clare","clare","clare"], keyTime = ["13:00","13:20","14:00","18:00","18:51","19:30","19:49"]
**Output:** ["clare","leslie"]
```

**Constraints:**

* `1 <= keyName.length, keyTime.length <= 105`
* `keyName.length == keyTime.length`
* `keyTime[i]` is in the format **"HH:MM"**.
* `[keyName[i], keyTime[i]]` is **unique**.
* `1 <= keyName[i].length <= 10`
* `keyName[i] contains only lowercase English letters.`

## ac

```java
```