import math
print("1:Vector po tochkam.2:Vector po koordinatam")
a=[]
b=[]
c=[]
k = int(input())
if k==1:
print("Vvedit` koordinaty tochki A(x,y)")
a.append(input())
a.append(input())
print("Vvedit` koordinaty tochki B(x,y)")
b.append(input())
b.append(input())
dovj1 = float (math.sqrt( (b[0]-a[0])*(b[0]-a[0]) + (b[1]-a[1])*(b[1]-a[1]) ))
print(dovj)
elif k==2:
print("Vvedit` koordinaty vectoru")
c.append(input())
c.append(input())
print(c[0])
print(c[1])
dovj2 = float(math.sqrt( c[0]*c[0] + c[1]*c[1] ))
print(dovj2)
print (s)