You are given an integer timer representing the remaining time (in seconds) on a traffic signal.
The signal follows these rules:
timer == 0, the signal is "Green"timer == 30, the signal is "Orange"30 < timer <= 90, the signal is "Red"Return the current state of the signal. If none of the above conditions are met, return "Invalid".
Example 1:
Input: timer = 60
Output: "Red"
Explanation:
Since timer = 60, and 30 < timer <= 90, the answer is "Red".
Example 2:
Input: timer = 5
Output: "Invalid"
Explanation:
Since timer = 5, it does not satisfy any of the given conditions, the answer is "Invalid".
Constraints:
0 <= timer <= 1000