Get Minimum Errors

Problem Overview

• Given a binary string with '0', '1', and '!' placeholders, choose each '!' as 0 or 1 to minimize total errors.
• An '01' subsequence adds x errors and a '10' subsequence adds y errors; return the minimum errors modulo 1e9+7.
• Input: errorString, integers x and y; Output: minimal error count as int.
• Domain: data integrity in Amazon's database; classic coding interview problem and interview question.
• Asked in Amazon interviews; constraints: 1 ≤ |s| ≤ 1e5, 0 ≤ x,y ≤ 1e5.