import sys

sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


N = I()
P = tuple(map(float,S().split()))
XYZ = [tuple(map(float,S().split())) for _ in range(N)]


def f(A,B,C,D):
    ax,ay,az = A
    bx,by,bz = B
    cx,cy,cz = C
    dx,dy,dz = D
    sx,sy,sz = (cy-by)*(dz-bz)-(cz-bz)*(dy-by),(cz-bz)*(dx-bx)-(cx-bx)*(dz-bz),(cx-bx)*(dy-by)-(cy-by)*(dx-bx)
    t = -(sx*bx+sy*by+sz*bz)
    return abs(sx*ax+sy*ay+sz*az+t)/((sx**2+sy**2+sz**2)**.5)


ans = 0
for i in range(N-2):
    for j in range(i+1,N-1):
        for k in range(j+1,N):
            ans += f(P,XYZ[i],XYZ[j],XYZ[k])

print(ans)