#from random import random

#x = round(random()* 1000,3)
#print(x)

x= float(input("Insert only floating point numbers only :"))

y = str(x)
maxi = -1

for i in range(len(y)):
    if y[i] == '.':
        continue
    elif maxi < int(y[i]):
        maxi = int(y[i])

print(" Maximum element is =", maxi)