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String to Integer (AtoI - ASCII to Integer) - Recursive Solution | Algorithms
Write a recursive function to implement atoi, which converts string to an integer. Rules for converting string to an integer. If the string is null or empty, Integer will be 0. The first character of the string may represent the sign of the integer. '+' or '-' Discard the white spaces if necessary. If String contains characters either before digits or after digits, ignore them.