Envío 586

Código

N =  int(input())
A = [eval(num) for num in input().split()]
sum_accum = [0] * N
sum_accum[-1] = A[-1]
for i in range(-N, -1)[::-1]:
    sum_accum[i] = A[i] + sum_accum[i+1]
if all([num > 0 for num in sum_accum]) or all([num < 0 for num in sum_accum]):
    print("Impossible")
else:
    for idx, num in enumerate(sum_accum):
        if num < 0:
            print(idx)
            break