FastPrep

Description

Solutions

Submission

Find Y Value

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Given a binary number as a string, x (a binary string), return the binary string of the same length, y, that will produce the maximum value when XORed with x. There is a number of bits that may be set in y called maxSet.

The binary strings will always have bits digits, and leading zeros are fine.

Function Description

Complete the function findYValue in the editor below.

findYValue has the following parameter(s):

1. int bits: the length of the binary strings x and y
2. int maxSet: the number of bits that may be set in y
3. string x: a binary string

Returns

string: the best y value as a binary string

Example 1:

Input:  bits = 3, maxSet = 1, x = "101"
Output: "010" 
Explanation:
First, determine all possible bits = 3 digit binary strings with only maxBits = 1 or fewer bits set: 000, 001, 010, 100. These are the potential y values.


Now, XOR each of the y values with x = 101:

  000 xor 101 = 101
  001 xor 101 = 100
  010 xor 101 = 111
  100 xor 101 = 001
       
The third value produces the maximal result, where y = 010. Return the string '010'.

Constraints:

Unknown for now