"Leetcode" Min Stack

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.

• Push (x)-push element x onto stack.
• Pop ()--Removes the element on top of the stack.
• Top ()--Get the top element.

• Getmin ()--Retrieve The minimum element in the stack

The key to this problem is how you save the numbers. In fact stack itself can be, but need to consider a problem: Join me push1,3,5,4,0, When the pop finishes 0 you need to go back to let min equals 1. So we should first push1 in the Push0, then Push0, so pop0, we pop0 before the 1 to the Min is good ~~~~~~

Import java.util.arraylist;import java.util.stack;class minstack {stack<integer> Stack = new Stack<Integer > (); int min;public static void main (String args[]) {minstack ms  = new Minstack (); Ms.push (0); Ms.push (1); Ms.push (0 ); System.out.println (Ms.getmin ()); Ms.pop ();//system.out.println (Ms.pop ();); System.out.println (Ms.getmin ());}    public void push (int x) {    if (stack.empty () | | | X<=min) {    stack.push (min);    Stack.push (x);    min = x;    }    else Stack.push (x);    }    public void Pop () {    int tmp = Stack.pop ();    if (tmp==min) Min=stack.pop ();    }    public int Top () {        return Stack.peek ();    }    public int getmin () {        return min;    }}

"Leetcode" Min Stack