lA.py

x1 = input("x1 ")
x1 = int(x1)
y1 = input("y1 ")
y1 = int(y1)
z1 = input("z1 ")
z1 = int(z1)

x2 = input("x2 ")
x2 = int(x2)
y2 = input("y2 ")
y2 = int(y2)
z2 = input("z2 ")
z2 = int(z2)

x3 = input("x3 ")
x3 = int(x3)
y3 = input("y3 ")
y3 = int(y3)
z3 = input("z3 ")
z3 = int(z3)

ser12 = ((x1 + x2)/2 , (y1 + y2)/2 , (z1 + z2)/2)
ser13 = ((x1 + x3)/2 , (y1 + y3)/2 , (z1 + z3)/2)
ser23 = ((x3 + x2)/2 , (y3 + y2)/2 , (z3 + z2)/2)
print("Центр 1 и 2 " , ser12  , '\n'
          "Центр 1 и 3 ", ser13 ,  '\n'
          "Центр 2 и 3 " , ser23 )
print("A = 1 , B = 2, C = 3")
longAB = math.sqrt((x1 - x2) **2)
print(longAB)