#!/usr/bin/python3
import math

def calculate_function(x):
	fx=None
	if x<=0:
		fx= 3*x**2 + 1
		print(f"timh ths synarthshs f gia x={x} einai ish me: {fx}")
	elif x>0 and x<=3:
		fx= 2*x +1
		print(f"timh ths synarthshs f gia x={x} einai ish me: {fx}")
	else:
		fx=math.sqrt(46+x)
		print(f"timh ths synarthshs f gia x={x} einai ish me: {fx}")

def main():
	x=float(input("Dwse arithmo x gia ypologismo ths synarthshs f: "))
	calculate_function(x)

if __name__=="__main__":
	main()