from sys import stdin
def main():
    #入力
    readline=stdin.readline
    a,b,c=map(int,readline().split())

    if max(a,b,c)==b:
        print(min(b-a,a-c))
    else:
        n=min(a,c)
        print(min(abs(c-a),n-b))

if __name__=="__main__":
    main()