def digitSum(x):
total = 0
while x>0:
total+=x%10
x=x//10
return total
def solve(A):
max_num = {}
ans = -1
for x in A:
s = digitSum(x)
if s in max_num:
ans = max(ans, max_num[s] + x)
max_num[s] = max(max_num.get(s,0), x)
return ans
def main():
n = int(input())
A = list(map(int, input().split()))
print(solve(A))
if __name__=="__main__":
main()
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