package main

type Interval struct {
  Min float64
  Max float64
}

func (i Interval) Size() float64 {
  return i.Max - i.Min;
}

func (i Interval) Include(x float64) bool {
  return i.Min <= x && x <= i.Max;
}

func (i Interval) Surround(x float64) bool {
  return i.Min < x && x < i.Max;
}