Code RoomPrime bit count range
EasyPrep Room Coding #984

Prime bit count range

CodingAlgorithms & data structuresEntry–Mid~15 min

Given an inclusive integer range [lo, hi] (0 <= lo <= hi <= 1e6), return how many integers v in the range have a prime number of set bits (1s) in their binary representation. For example 6 is 110 (2 set bits, prime) and 7 is 111 (3 set bits, prime). Note 1 set bit is not prime.

Implement
count_prime_set_bits(lo: int, hi: int) → int
Examples
in[6,10]out4
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 15 min
InputExpectedGot
[6,10]4not run yetsample