public class MinStack {
     
    int min = Integer.MAX_VALUE;
    Stack<Integer> stack = new Stack<Integer>();
    /** initialize your data structure here. */
    public MinStack() {
        
    }
    
    public void push(int x) {
        if(x <= min){          
            stack.push(min);
            min=x;
        }
        stack.push(x);
    }
    
    public void pop() {
         if(stack.pop() == min) min=stack.pop();
    }
    
    public int top() {
       return stack.peek(); 
    }
    
    public int getMin() {
        return min;
    }
}

/**
 * Your MinStack object will be instantiated and called as such:
 * MinStack obj = new MinStack();
 * obj.push(x);
 * obj.pop();
 * int param_3 = obj.top();
 * int param_4 = obj.getMin();
 */