Bài 3: độ dài đoạn thẳng 2
from math import sqrt
x1 = int(input())
x2 = int(input())
x3 = int(input())
y1 = int(input())
y2 = int(input())
y3 = int(input())
Dab = sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1))
Dbc = sqrt((x3-x2)*(x3-x2)+(y3-y2)*(y3-y2))
Dac = sqrt((x3-x1)*(x3-x1)+(y3-y1)*(y3-y1))
print("{:.3}".format(Dab))
print("{:.3}".format(Dbc))
print("{:.3}".format(Dac))