package main

import (
	"fmt"
	"math"
)

func main() {

	// 4 7 3
	var a, b, c int
	fmt.Scan(&a, &b, &c)
	cal1 := float64(b - a)
	cal2 := float64(b - c)
	cal3 := math.Abs(float64(a - c))

	fmt.Println(math.Min(math.Min(cal1, cal2), cal3))


}