package lastack import ( "focus/stack" "github.com/davecgh/go-spew/spew" ) type Node struct { value interface{} down *Node } type Stack struct { top *Node size uint } func assertImplementation() { var _ stack.IStack = (*Stack)(nil) } func New() *Stack { s := &Stack{} s.size = 0 return s } func (as *Stack) Clear() { as.size = 0 as.top = nil } func (as *Stack) Empty() bool { return as.size == 0 } func (as *Stack) Size() uint { return as.size } // String 从左到右 左边第一个表示Top 如链表 a(top)->b->c func (as *Stack) String() string { content := "" cur := as.top for ; cur != nil; cur = cur.down { content += spew.Sprint(cur.value) + " " } if len(content) > 0 { content = content[0 : len(content)-1] } else { content = "" } return content } func (as *Stack) Values() []interface{} { if as.size == 0 { return nil } result := make([]interface{}, as.size, as.size) cur := as.top n := 0 for ; cur != nil; cur = cur.down { result[n] = cur.value n++ } return result } func (as *Stack) Push(v interface{}) { nv := &Node{value: v} nv.down = as.top as.top = nv as.size++ } func (as *Stack) Pop() (interface{}, bool) { if as.size == 0 { return nil, false } as.size-- result := as.top as.top = as.top.down result.down = nil return result.value, true } func (as *Stack) Peek() (interface{}, bool) { if as.size == 0 { return nil, false } return as.top.value, true }