class Solution:
def countPrimeSetBits(self, L: int, R: int) -> int:
res = 0
prime = set([2, 3, 5, 7, 11, 13, 17, 19]) #转成set,查找比list快一些
set_bit = 0 #计算置位
for i in range(L, R+1):
set_bit = 0
while i > 0:
set_bit += i & 1
i >>= 1
if set_bit in prime: #查找是否为素数
res += 1
return res