package main
import "fmt"
func makeSet() *customSet {
return &customSet{
container: make(map[string]struct{}),
}
}
type customSet struct {
container map[string]struct{}
}
func (c *customSet) Exists(key string) bool {
_, exists := c.container[key]
return exists
}
func (c *customSet) Add(key string) {
c.container[key] = struct{}{}
}
func (c *customSet) Remove(key string) error {
_, exists := c.container[key]
if !exists {
return fmt.Errorf("Remove Error: Item doesn't exist in set")
}
delete(c.container, key)
return nil
}
func (c *customSet) Size() int {
return len(c.container)
}
func (c *customSet) Print() {
for k, v := range c.container {
fmt.Println(k, v)
}
}
func main() {
customSet := makeSet()
fmt.Printf("Add: A\n")
customSet.Add("A")
fmt.Printf("Add: B\n")
customSet.Add("B")
fmt.Printf("Size: %d\n", customSet.Size())
fmt.Printf("C exists? %t\n", customSet.Exists("C"))
customSet.Print()
}
