Description

Implement atoi which converts a string to a 32-bit signed integer (similar to C/C++ atoi).

• Read in and ignore any leading whitespace.
• Optional '+' or '-' sign.
• Read in next characters until the next non-digit character or end of input; convert these digits to an integer.
• If no digits were read, return 0.
• Clamp the integer to the 32-bit signed integer range: [-2^31, 2^31 - 1].

Example 1:

Example 2:

Example 3:

Note:

Runner reads a single line string from stdin and expects a single integer printed to stdout (e.g. input: -42 → output: -42).