EASY

3168. Minimum Number of Chairs in a Waiting Room

You are given a string s representing the sequence of arrivals and departures in a waiting room. Each character is either 'E' (enter) or 'L' (leave). Return the minimum number of chairs needed so that no one has to stand at any time.

Example

Input:

s = "ELEELEELLL"

Output:

Explanation: At most 2 people are in the room at the same time.

Constraints

1 ≤ s.length ≤ 100
s consists only of 'E' and 'L'.

Solution: Simulation

Time Complexity: O(n), where n is the length of s.
Space Complexity: O(1)

C++

class Solution {
public:
    int minimumChairs(string s) {
        int curr = 0, res = 0;
        for (char c : s) {
            if (c == 'E') curr++;
            else curr--;
            res = max(res, curr);
        }
        return res;
    }
};