Description:
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.
带有minimum element属性的stack操作。
class MinStack {
public Node node = null;
public void push(int x) {
if(node == null) {
node = new Node(x);
node.min = x;
}
else {
Node tNode = new Node(x);
tNode.next = node;
node = tNode;
node.min = node.next.min < x ? node.next.min : x;
}
} public void pop() {
node = node.next;
} public int top() {
return node.val;
} public int getMin() {
return node.min;
}
}
class Node {
int val;
int min;
Node next;
public Node(int val) {
this.val = val;
}}
好久没1A了。