I knew the add-strings pattern going in, integer version is pretty standard.
Clarify that the core challenge is simulating decimal addition without numeric conversion. Propose splitting the strings into integer and fractional parts, padding the fractional parts to equal length, then performing digit-by-digit addition from right to left with carry handling. Finally, strip trailing zeros from the fractional part and combine with the integer sum.
Pro tip: Mention that you would first ask about constraints (e.g., maximum length, presence of leading zeros) to decide between a simple simulation and a more optimized approach. Also, emphasize that you would write helper functions for string reversal and carry propagation to keep the code clean and testable.
Ask about input constraints (e.g., max length, leading zeros, empty strings) and confirm that the result should be a string with trailing zeros stripped. Discuss edge cases like '0.0', '0', and numbers with no decimal point.
Split each string into integer and fractional parts. Pad the fractional parts with zeros on the right so they have equal length. Also, pad the integer parts with leading zeros on the left to equalize their lengths.
Iterate from the end of the fractional parts to the beginning, summing digits and propagating carry. Store the result in a list or string builder.
Continue the addition with the integer parts, starting from the least significant digit, including any carry from the fractional part. Handle the final carry if it remains.
Combine the integer and fractional results, remove trailing zeros from the fractional part, and omit the decimal point if the fractional part becomes empty. Return the final string.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.