a = [0] * 100
for i in range(50, 101):
    s = bin(i)[2:]
    if s.count('1') > s.count('0'):
        s += '0'
    else:
        s += '1'
    l = len(s) // 2
    s = s[:l-1] + s[l + 1 + (len(s) % 2):]
    a[int(s,2)] = 1

print(a.count(1))