beginner
11 min read
Add Binary
You receive two binary strings, a and b, and must return their sum as another binary string. The inputs contain only '0' and '1', have lengths from 1 to…
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Digit-by-Digit Arithmetic
Perform arithmetic or numeric transformation directly over a digit representation, maintaining position-wise state such as carry, borrow, partial products, or reconstructed digits.
Tagged articles
Digit-by-Digit Arithmetic articles
4 articles in this tag.
intermediate
10 min read
Add Two Numbers
The lists already expose digits in the order addition needs. Scan both lists together, track one carry, and keep going until there is no digit or carry…
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intermediate
10 min read
Multiply Strings
Treat the product as a fixed array of decimal positions. Every digit pair has a predictable destination; carry normalization keeps those positions valid.
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beginner
9 min read
Plus One
Adding one looks trivial until the last digit is 9. Then the problem becomes a compact state-tracking exercise: start where arithmetic begins, propagate a…
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