单调栈的最大宽度

• 单调栈的最大宽度：
• 1 2 6 3 5 7
• 1 2 6
• 3 5 7
• max=10

     public static void getMaxWidth(int[] arr){
      	Stack<Integer> stack=new Stack<Integer>();
     	 int max=0;
     	 int len=1;
      	for(int i=0;i<arr.length;i++){
       	if((!stack.isEmpty()&&stack.peek()<arr[i])||stack.isEmpty()){
       		 stack.push(arr[i]);
      	 }
       	if(!stack.isEmpty()&&stack.peek()>arr[i]||i==arr.length-1){
        		while(!stack.isEmpty()){
         			int tmp=stack.pop()*len;
         			max=tmp>max?tmp:max;
         			len++;
        		}
        		len=1;
        		stack.push(arr[i]);
       	}
      }
      System.out.println(max);
     }