You are given a string s. Simulate events at each second i:
s[i] == 'E', a person enters the waiting room and takes one of the chairs in it.s[i] == 'L', a person leaves the waiting room, freeing up a chair.Return the minimum number of chairs needed so that a chair is available for every person who enters the waiting room given that it is initially empty.
\n\n\n
Example 1:
\n\nInput: s = "EEEEEEE"
\n\nOutput: 7
\n\nExplanation:
\n\nAfter each second, a person enters the waiting room and no person leaves it. Therefore, a minimum of 7 chairs is needed.
\nExample 2:
\n\nInput: s = "ELELEEL"
\n\nOutput: 2
\n\nExplanation:
\n\nLet's consider that there are 2 chairs in the waiting room. The table below shows the state of the waiting room at each second.
\n| Second | \n\t\t\tEvent | \n\t\t\tPeople in the Waiting Room | \n\t\t\tAvailable Chairs | \n\t\t
|---|---|---|---|
| 0 | \n\t\t\tEnter | \n\t\t\t1 | \n\t\t\t1 | \n\t\t
| 1 | \n\t\t\tLeave | \n\t\t\t0 | \n\t\t\t2 | \n\t\t
| 2 | \n\t\t\tEnter | \n\t\t\t1 | \n\t\t\t1 | \n\t\t
| 3 | \n\t\t\tLeave | \n\t\t\t0 | \n\t\t\t2 | \n\t\t
| 4 | \n\t\t\tEnter | \n\t\t\t1 | \n\t\t\t1 | \n\t\t
| 5 | \n\t\t\tEnter | \n\t\t\t2 | \n\t\t\t0 | \n\t\t
| 6 | \n\t\t\tLeave | \n\t\t\t1 | \n\t\t\t1 | \n\t\t
Example 3:
\n\nInput: s = "ELEELEELLL"
\n\nOutput: 3
\n\nExplanation:
\n\nLet's consider that there are 3 chairs in the waiting room. The table below shows the state of the waiting room at each second.
\n| Second | \n\t\t\tEvent | \n\t\t\tPeople in the Waiting Room | \n\t\t\tAvailable Chairs | \n\t\t
|---|---|---|---|
| 0 | \n\t\t\tEnter | \n\t\t\t1 | \n\t\t\t2 | \n\t\t
| 1 | \n\t\t\tLeave | \n\t\t\t0 | \n\t\t\t3 | \n\t\t
| 2 | \n\t\t\tEnter | \n\t\t\t1 | \n\t\t\t2 | \n\t\t
| 3 | \n\t\t\tEnter | \n\t\t\t2 | \n\t\t\t1 | \n\t\t
| 4 | \n\t\t\tLeave | \n\t\t\t1 | \n\t\t\t2 | \n\t\t
| 5 | \n\t\t\tEnter | \n\t\t\t2 | \n\t\t\t1 | \n\t\t
| 6 | \n\t\t\tEnter | \n\t\t\t3 | \n\t\t\t0 | \n\t\t
| 7 | \n\t\t\tLeave | \n\t\t\t2 | \n\t\t\t1 | \n\t\t
| 8 | \n\t\t\tLeave | \n\t\t\t1 | \n\t\t\t2 | \n\t\t
| 9 | \n\t\t\tLeave | \n\t\t\t0 | \n\t\t\t3 | \n\t\t
\n
Constraints:
\n\n1 <= s.length <= 50s consists only of the letters 'E' and 'L'.s represents a valid sequence of entries and exits.Compiled with clang 17 using the latest C++ 20 standard, and libstdc++ provided by GCC 11.
Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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Python 2.7.12.
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