n = int(input())
l = [*map(int, input().split())]
cap = 98
prev = 2
crt = l[0]
for i in range(1, n):
if crt == l[i]:
prev *= 2
else:
prev = 2
crt = l[i]
cap -= prev
if cap <= 0:
crt = -1
cap = 100
print(100 - cap)