String to Integer (atoi)

Implement the `myAtoi(string s)` function, which converts a string to a 32-bit signed integer. The algorithm for `myAtoi(string s)` is as follows: - **Whitespace**: Ignore any leading whitespace (`" "`). - **Signedness**: Determine the sign by checking if the next character is `'-'` or `'+'`, assuming positivity if neither present. - **Conversion**: Read the integer by skipping leading zeros until a non-digit character is encountered or the end of the string is reached. If no digits were read, then the result is 0. - **Rounding**: If the integer is out of the 32-bit signed integer range `[-231, 231 - 1]`, then round the integer to remain in the range. Specifically, integers less than `-231` should be rounded to `-231`, and integers greater than `231 - 1` should be rounded to `231 - 1`. Return the integer as the final result.   **Example 1:** **Input:** s = "42" **Output:** 42 **Explanation:** The underlined characters are what is read in and the caret is the current reader position. Step 1: "42" (no characters read because there is no leading whitespace) ^ Step 2: "42" (no characters read because there is neither a '-' nor '+') ^ Step 3: "42" ("42" is read in) ^ ``` **Example 2:** **Input:** s = " -042" **Output:** -42 **Explanation:** Step 1: " -042" (leading whitespace is read and ignored) ^ Step 2: " -042" ('-' is read, so the result should be negative) ^ Step 3: " -042" ("042" is read in, leading zeros ignored in the result) ^ ``` **Example 3:** **Input:** s = "1337c0d3" **Output:** 1337 **Explanation:** Step 1: "1337c0d3" (no characters read because there is no leading whitespace) ^ Step 2: "1337c0d3" (no characters read because there is neither a '-' nor '+') ^ Step 3: "1337c0d3" ("1337" is read in; reading stops because the next character is a non-digit) ^ ``` **Example 4:** **Input:** s = "0-1" **Output:** 0 **Explanation:** Step 1: "0-1" (no characters read because there is no leading whitespace) ^ Step 2: "0-1" (no characters read because there is neither a '-' nor '+') ^ Step 3: "0-1" ("0" is read in; reading stops because the next character is a non-digit) ^ ``` **Example 5:** **Input:** s = "words and 987" **Output:** 0 **Explanation:** Reading stops at the first non-digit character 'w'.   **Constraints:** - `0 <= s.length <= 200` - `s` consists of English letters (lower-case and upper-case), digits (`0-9`), `' '`, `'+'`, `'-'`, and `'.'`.