730. Convert Binary to Decimal Using Recursion

Given a binary string s (containing only characters '0' and '1', optionally prefixed with '-' to indicate a negative number), return the integer value it represents. The most significant bit is on the left. Implement the conversion recursively. You may assume the result fits in a 64-bit signed integer.

Input: A non-empty binary string s enclosed in double quotes.

Output: Return an integer equal to the decimal value of s.

Examples

Input: "1010"
Output: 10
Explanation: 1*8 + 0*4 + 1*2 + 0*1 = 10.

Input: "0"
Output: 0
Explanation: Zero.

Input: "-101"
Output: -5
Explanation: Binary 101 is 5; the minus sign makes it -5.

Constraints

• 1 <= s.length <= 31 (after optional sign)
• s contains only '0', '1', and optionally a leading '-'

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