from math import acos, tan, hypot



def getRad1(s12, s13, s23):

    return acos((s12*s12 + s13*s13 - s23*s23) / (2*s12*s13))



def getMaxR(s12, rad1, rad2):

    tan1 = tan(rad1 / 2)

    tan2 = tan(rad2 / 2)

    h = s12 * (tan1*tan2) / (tan1+tan2)

    return h * (tan1+tan2) / (2*tan1*tan2 + tan1 + tan2)



x1, y1 = list(map(int, input().split()))

x2, y2 = list(map(int, input().split()))

x3, y3 = list(map(int, input().split()))



s12 = hypot(x1-x2, y1-y2)

s23 = hypot(x2-x3, y2-y3)

s31 = hypot(x3-x1, y3-y1)



rad1 = getRad1(s12, s31, s23)

rad2 = getRad1(s23, s12, s31)

rad3 = getRad1(s31, s23, s12)



maxRs = [

    getMaxR(s12, rad1, rad2), 

    getMaxR(s23, rad2, rad3),

    getMaxR(s31, rad3, rad1)

]

print((max(maxRs)))

from math import acos, tan, hypot



def getRad1(s12, s13, s23):

    return acos((s12*s12 + s13*s13 - s23*s23) / (2*s12*s13))



def getMaxR(s12, rad1, rad2):

    tan1 = tan(rad1 / 2)

    tan2 = tan(rad2 / 2)

    h = s12 * (tan1*tan2) / (tan1+tan2)



    def isOK(mid):

        return s12 - mid/tan1 - mid/tan2 <= 2*mid



    ng, ok = 0, h

    while abs(ok-ng) > 10**-12:

        mid = (ng+ok) / 2

        if isOK(mid):

            ok = mid

        else:

            ng = mid

    return ok



x1, y1 = list(map(int, input().split()))

x2, y2 = list(map(int, input().split()))

x3, y3 = list(map(int, input().split()))



s12 = hypot(x1-x2, y1-y2)

s23 = hypot(x2-x3, y2-y3)

s31 = hypot(x3-x1, y3-y1)



rad1 = getRad1(s12, s31, s23)

rad2 = getRad1(s23, s12, s31)

rad3 = getRad1(s31, s23, s12)



maxRs = [

    getMaxR(s12, rad1, rad2), 

    getMaxR(s23, rad2, rad3),

    getMaxR(s31, rad3, rad1)

]

print((max(maxRs)))

from math import acos, tan, hypot


def getRad1(s12, s13, s23):
    return acos((s12 * s12 + s13 * s13 - s23 * s23) / (2 * s12 * s13))


def getMaxR(s12, rad1, rad2):
    tan1 = tan(rad1 / 2)
    tan2 = tan(rad2 / 2)
    h = s12 * (tan1 * tan2) / (tan1 + tan2)
    return h * (tan1 + tan2) / (2 * tan1 * tan2 + tan1 + tan2)


x1, y1 = list(map(int, input().split()))
x2, y2 = list(map(int, input().split()))
x3, y3 = list(map(int, input().split()))
s12 = hypot(x1 - x2, y1 - y2)
s23 = hypot(x2 - x3, y2 - y3)
s31 = hypot(x3 - x1, y3 - y1)
rad1 = getRad1(s12, s31, s23)
rad2 = getRad1(s23, s12, s31)
rad3 = getRad1(s31, s23, s12)
maxRs = [getMaxR(s12, rad1, rad2), getMaxR(s23, rad2, rad3), getMaxR(s31, rad3, rad1)]
print((max(maxRs)))

from math import acos, tan, hypot


def getRad1(s12, s13, s23):
    return acos((s12 * s12 + s13 * s13 - s23 * s23) / (2 * s12 * s13))


def getMaxR(s12, rad1, rad2):
    tan1 = tan(rad1 / 2)
    tan2 = tan(rad2 / 2)
    h = s12 * (tan1 * tan2) / (tan1 + tan2)

    def isOK(mid):
        return s12 - mid / tan1 - mid / tan2 <= 2 * mid

    ng, ok = 0, h
    while abs(ok - ng) > 10**-12:
        mid = (ng + ok) / 2
        if isOK(mid):
            ok = mid
        else:
            ng = mid
    return ok


x1, y1 = list(map(int, input().split()))
x2, y2 = list(map(int, input().split()))
x3, y3 = list(map(int, input().split()))
s12 = hypot(x1 - x2, y1 - y2)
s23 = hypot(x2 - x3, y2 - y3)
s31 = hypot(x3 - x1, y3 - y1)
rad1 = getRad1(s12, s31, s23)
rad2 = getRad1(s23, s12, s31)
rad3 = getRad1(s31, s23, s12)
maxRs = [getMaxR(s12, rad1, rad2), getMaxR(s23, rad2, rad3), getMaxR(s31, rad3, rad1)]
print((max(maxRs)))

-    return h * (tan1 + tan2) / (2 * tan1 * tan2 + tan1 + tan2) + +    def isOK(mid): +        return s12 - mid / tan1 - mid / tan2 <= 2 * mid + +    ng, ok = 0, h +    while abs(ok - ng) > 10**-12: +        mid = (ng + ok) / 2 +        if isOK(mid): +            ok = mid +        else: +            ng = mid +    return ok