55 lines
883 B
Go
55 lines
883 B
Go
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package stack
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import "errors"
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//使用链表实现栈
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//以下是使用单向链表，使用头插法实现，也可以使用标准库的双向链表实现
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//节点，需要动态申请内存空间
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type Node struct {
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data int
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next *Node
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}
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//栈
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type ListStack struct {
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top *Node
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}
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func NewListStack() *ListStack {
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return &ListStack{}
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}
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//是否为空
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func (ls *ListStack) IsEmpty() bool {
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return ls.top == nil
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}
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//入栈,头插法
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func (ls *ListStack) Push(i int) {
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//新建节点
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n := &Node{i, nil}
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if ls.top != nil {
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n.next = ls.top
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}
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ls.top = n
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}
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//出栈,从头弹出
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func (ls *ListStack) Pop() (int, error) {
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if ls.top == nil {
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return 0, errors.New("栈空")
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}
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i := ls.top.data
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ls.top = ls.top.next
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return i, nil
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}
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//查看
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func (ls *ListStack) Peek() (int, error) {
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if ls.top == nil {
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return 0, errors.New("栈空")
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}
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return ls.top.data, nil
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}
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