# 1004.py

def f(x): return 2*x+1

def g(x):
  if x>0: return x
  return -x

for x in xrange(10): print f(x),
print
# output: 1 3 5 7 9 11 13 15 17 19

for x in xrange(-5,5): print g(x),
print
# output: 5 4 3 2 1 0 1 2 3 4
#######################################
import math

def raggio (x,y):
  return math.sqrt(x**2+y**2)

print raggio(2,3)
# output: 3.60555127546

print math.sqrt(13)
# output: 3.60555127546