设计包含min函数的栈。

/*
设计包含min函数的栈。
定义栈的数据结构，要求添加一个min函数，能够得到栈的最小元素。
要求函数min、push以及pop的时间复杂度都是O(1)。


*/ 
#include<iostream>
using namespace std;
class Stack{
private:
int *stack;
int top = -1;
int topmin = -1;
int size;
int *minstack;
public:
Stack(int size) {
stack = (int *)malloc(sizeof(int)*size);
minstack = (int *)malloc(sizeof(int)*size);
this->size = 0;
}
void push(int data);
int pop();
int min();
};
void Stack::push(int data){
if (top == -1){
stack[++top] = data;
minstack[++topmin] = top;
size++;
}
else {
stack[++top] = data;
size++;
if (data < stack[minstack[topmin]]){
minstack[++topmin] = top;
}
else {
int top1 = minstack[topmin];
minstack[++topmin] = top1;
}
}
}
int Stack::pop(){
int topvalue;
topvalue = stack[top--];
topmin--;
return topvalue;
}
int Stack::min(){
return stack[minstack[topmin]];
}
int main(void)
{
Stack *s = new Stack(50);
int data;
for (int i = 0; i < 10; i++){
cin >> data;
s->push(data);
}
s->min();
for (int i = 0; i < 10; i++)
{
cout << s->min();
cout << s->pop() << endl;
}
/* cout << s->min();
cout << s->pop() << endl;
cout << s->min();
cout << s->pop() << endl;
cout << s->min();
cout << s->pop() << endl;
cout << s->min();
cout << s->pop() << endl;*/
return 0;
}