leetcode 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/

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 are in the format “HH:MM”.
[keyName[i], keyTime[i]] is unique.
1 <= keyName[i].length <= 10
keyName[i] contains only lowercase English letters.

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class Solution {
public:
vector<string> alertNames(vector<string>& keyName, vector<string>& keyTime) {
unordered_map<string, vector<int>> maps;

int size = keyName.size();

for (int i = 0; i < size; i++) {
int time = stoi(keyTime[i].substr(0, 2)) * 60 + stoi(keyTime[i].substr(3));
maps[keyName[i]].push_back(time);
}

vector<string> result;

for (auto v : maps) {
sort(v.second.begin(), v.second.end());

int i = 0;
for (int j = 1; j < v.second.size(); j++) {
while (v.second[j] - v.second[i] > 60) {
i++;
}

if (j - i + 1 >= 3) {
result.push_back(v.first);
break;
}
}
}

sort(result.begin(), result.end());

return result;
}
};