package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"sort"
	"strconv"
)

func out(x ...interface{}) {
	fmt.Println(x...)
}

var sc = bufio.NewScanner(os.Stdin)

func getInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func getInts(N int) []int {
	ret := make([]int, N)
	for i := 0; i < N; i++ {
		ret[i] = getInt()
	}
	return ret
}

func getString() string {
	sc.Scan()
	return sc.Text()
}

// min, max, asub, absなど基本関数
func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func asub(a, b int) int {
	if a > b {
		return a - b
	}
	return b - a
}

func abs(a int) int {
	if a >= 0 {
		return a
	}
	return -a
}

func lowerBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] >= x
	})
	return idx
}

func upperBound(a []int, x int) int {
	idx := sort.Search(len(a), func(i int) bool {
		return a[i] > x
	})
	return idx
}

func calcL(x0, y0, z0, x1, y1, z1, x2, y2, z2, x3, y3, z3 float64) float64 {
	ax := x2 - x1
	ay := y2 - y1
	az := z2 - z1
	bx := x3 - x1
	by := y3 - y1
	bz := z3 - z1

	// out(x1, y1, z1)
	// out(x2, y2, z2)
	// out(x3, y3, z3)
	// out(ax, ay, az, bx, by, bz)
	a := ay*bz - az*by
	b := az*bx - ax*bz
	c := ax*by - ay*bx
	d := -(a*x1 + b*y1 + c*z1)

	// out(a, b, c, d)

	ret := math.Abs(a*x0 + b*y0 + c*z0 + d)
	ret /= math.Sqrt(a*a + b*b + c*c)

	return ret
}

func getf() float64 {
	sc.Scan()
	f, _ := strconv.ParseFloat(sc.Text(), 64)
	return f
}

func main() {
	sc.Split(bufio.ScanWords)
	sc.Buffer([]byte{}, 1000000)
	N := getInt()
	x, y, z := getf(), getf(), getf()
	f := make([][3]float64, N)
	for i := 0; i < N; i++ {
		f[i][0], f[i][1], f[i][2] = getf(), getf(), getf()
	}

	ans := 0.0

	for i := 0; i < N; i++ {
		for j := i + 1; j < N; j++ {
			for k := j + 1; k < N; k++ {
				ret := calcL(x, y, z,
					f[i][0], f[i][1], f[i][2],
					f[j][0], f[j][1], f[j][2],
					f[k][0], f[k][1], f[k][2],
				)
				out(i, j, k, ret)
				ans += ret
			}
		}
	}
	out(ans)
}