class MinStack {

	Node stack;
	int size;

	public void push(int data) {
		Node node = new Node(data);
		node.next = stack;
		stack = node;
		size++;
	}

	public void pop() {
		stack = stack.next;
		size--;
	}

	public int top() {
		return stack.data;
	}

	public int getMin() {
		Node node = stack;
		int min = node.data;
		while (node.next != null) {
			node = node.next;
			if (node.data < min)
				min = node.data;
		}
		return min;
	}

	class Node {

		int data;
		Node next;

		public Node(int data) {
			this.data = data;
		}
	}
}