剑指offer题解 包含min函数的栈

import java.util.Stack;

public class Solution {
Stack<Integer> mStack=new Stack();
Stack<Integer> mMinNum=new Stack();

public void push(int node) {
mStack.push(node);
if(mMinNum.empty()||mMinNum.peek()>node){
mMinNum.push(node);
}else{
mMinNum.push(mMinNum.peek());
}
}

public void pop() {
mStack.pop();
mMinNum.pop();
}

public int top() {
return mStack.peek();
}

public int min() {
return mMinNum.peek();
}
}