Build the PrimitiveEasy
Two Sum
Write `two_sum(nums, target)` that returns the indices of the two values summing to `target`, as a tuple `(i, j)` with `i < j`. Exactly one such pair exists.
two_sum([2, 7, 11, 15], 9) -> (0, 1)
two_sum([3, 3], 6) -> (0, 1)
The trick is a map from value to index built as you go. Look up the complement *before* inserting the current value, or a single element will pair with itself.
What to expect: A timer starts when you begin. Edit the starter code, run it against the test suite as many times as you like, then finish when you're done. The reference solution and interviewer follow-up questions unlock only after you finish.