N = int(input())
V = input().rstrip().split(" ")
v = []
for i in range(N):
    v[i] = int(V[i])
value = [0] * N
value[1] = v[0]
for i in range(2,N):
    value[i] = max(value[i-1],value[i - 2] + v[i-1])
print(value)