Brute Force(暴力)
class Solution(object):
def powerfulIntegers(self, x, y, bound):
"""
:type x: int
:type y: int
:type bound: int
:rtype: List[int]
"""
ans=[] for i in range(20):
for j in range(20):
a=x**i+y**j
if a<=bound:
ans.append(a) return list(set(ans))