code: func RandomInt(n int) int {
  	if n <= 0 {
  		panic(fmt.Sprintf("Got invalid (non positive) value: %d", n))
  	}
  	m := int(RandomUInt64()) % n
  	if m < 0 {
  		return n + m
  	}
  	return m
  }
docs: // RandomInt returns, as an int, a non-negative pseudo-random integer in [0,n)
  // It panics if n <= 0