func (s *Float64) Remove(num float64) bool {
	_, ok := s.nodeMap[num]
	if ok {
		delete(s.nodeMap, num)
	}
	return ok
}
Remove given item
package set
type Float64 struct {
	nodeMap map[float64]struct{}
}
func NewFloat64(nums []float64) *Float64 {
	s := &Float64{}
	for _, num := range nums {
		s.Add(num)
	}
	return s
}
func (s *Float64) Add(num float64) *Float64 {
	if s.nodeMap == nil {
		s.nodeMap = make(map[float64]struct{})
	}
	_, ok := s.nodeMap[num]
	if !ok {
		s.nodeMap[num] = struct{}{}
	}
	return s
}
func (s *Float64) Clear() {
	s.nodeMap = make(map[float64]struct{})
}