Evaluate Increment and Decrement Commands

### Problem The integer variable `X` starts at 0. Each entry of `operations` is `++X`, `X++`, `--X` or `X--`. The first two increase X by one; the other two decrease it by one. Return its value after all commands have been applied. ```cpp class Solution { public: int finalValueAfterOperations(vector<string>& operations); }; ``` ### Examples **Example 1:** ```text operations = ["X--","--X","++X"] Output: -1 Explanation: The values are -1, -2, then -1. ``` **Example 2:** ```text operations = ["++X","X--"] Output: 0 Explanation: One increment and one decrement cancel. ``` ### Constraints - `1 <= operations.length <= 100`. - Every command is exactly `++X`, `X++`, `--X`, or `X--`. ### Clarifying Questions Prefix and postfix spellings have the same effect here because no expression uses the old or new value. ```hint Inspect the structure Which fixed character position distinguishes increments from decrements in all four spellings? ``` ### Reasoning checkpoints - Interpret all four permitted spellings with the stated initial value and effect. - Handle negative intermediate values and cancellation across the complete command list. ### Optional extensions Would reordering this particular command list change the final result?