Original problem · C++ solution
Define the given polynomial once and preserve the exact nesting of its calls.
Define the given polynomial once and preserve the exact nesting of its calls. Use 64-bit intermediates for squared values.
- Time: O(1).
- Extra space: O(1).
The types of operands control intermediate arithmetic. Read large values into long long before forming sums, products, or differences so the arithmetic itself uses 64 bits.
Integer division truncates toward zero; floor and ceiling formulas need special care for negative values.
State the invariant without looking at the code. Give one input that breaks the most tempting incorrect approach, then add it to the tests.