Missing Digits in Configuration

Problem Statement

Missing Digits in Configuration Problem Description The software developers at Amazon are working on detecting configuration anomalies in a server. They are provided with a set of configurations represented by config , a string of concatenated decimal digits (0-9). However, some digits in these configurations have been inadvertently erased. These configurations were initially generated using a specific procedure involving two integer parameters, x and y . The procedure begins with the two numbers, x and y , and initializes a current value ( cur ) to 0. The following operation can be performed any number of times. In each step, either x or y is added to cur . Compute the unit digit of ( cur % 10) after each addition. Record this digit as part of the configuration sequence. Unfortunately, some of these recorded digits are missing due to data corruption, complicating the reconstruction of the original sequence. Additionally, it is known that the first character of each given configuration