numStr to store the numerical representation of the input string s.s:
a. Convert the character to its corresponding number (1-26) by subtracting the ASCII value of 'a' and adding 1.
b. Append this number to numStr.k times:
a. Initialize sum to 0.
b. Iterate over each character in numStr and add its integer value to sum.
c. Convert sum back to a string and assign it to numStr.k iterations, convert numStr to an integer and return it as the result.