# coding: utf-8
# Here your code !

import math

x,y,r = input().split()
x = int(x)
y = int(y)
r = int(r)

o = 0
o += math.fabs(x)
o += math.fabs(y)
o += math.fabs(r * math.sqrt(2))
o = math.ceil(o)
o = int(o)
print(o)