-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathO1stack.cpp
More file actions
76 lines (62 loc) · 1.2 KB
/
Copy pathO1stack.cpp
File metadata and controls
76 lines (62 loc) · 1.2 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
/*
设计一个栈，使它们在O(1)的时间复杂度内实现push,pop,max的操作
*/
#include<iostream>
#include<vector>
using namespace std;
#define N 9
class myStack{
private:
vector<int>v;//实际的栈
vector<int>maxStack;//储存当前最大值的栈,和实际的栈同步
int top = -1;//记录当前的个数
int max = 0;//记录最大值
public:
myStack(){
}
int pop(){
//出栈方法
if(this->v.size() == 0){
cout<<"null stack"<<endl;
return -1;
}else{
this->maxStack.pop_back();
int x = this->v[top];
this->top--;
this->v.pop_back();
return x;
}
}
void push(int n){
//入栈方法
top++;
if(this->v.size() == 0 || this->max < n){
this->max = n;
}
this->v.push_back(n);
this->maxStack.push_back(this->max);
}
int getMax(){
//获取最大值
if(this->v.size() == 0){
cout<<"stack with no entry!"<<endl;
return -1;
}else{
return this->maxStack[top];
}
}
};
int main(){
myStack ms;
ms.pop();
ms.getMax();
int x[] = {1,10,6,13,7,8,25,11,19};
for(int i = 0; i < N; i++){
ms.push(x[i]);
cout<<"push "<<x[i]<<" and now max is : "<<ms.getMax()<<endl;
}
for(int i = 0; i < 5; i++){
cout<<"pop "<<ms.pop()<<" and now max is : "<<ms.getMax()<<endl;
}
return 0;
}