def solution(a, b):
answer = 0
for i in range(len(a)):
answer += a[i]*b[i]
return answer
def solution(n):
m = []
answer = 0
while(n>=1) :
m.append(int(n%3))
n /= 3
for i in range(len(m)):
answer += m[i]*(3**(len(m)-(i+1)))
return answer
from itertools import permutations
def solution(numbers):
answer = sorted(list(set(list(map(sum, list(permutations(numbers,2)))))))
return answer