螺旋打印2D数组

//一破题付出血的代价   多思考！
public static void offer(int [][]a){
       int left=,right=a.length-,low=,high=a[].length-;
       while(low<=high){
            for(int i=left;i<=right;i++){//
                System.out.print(a[left][i]+" ");
            }
            low++;
           for(int i=low;i<=high;i++){//
               System.out.print(a[i][right]+" ");
           }
           right--;
           for(int i=right;i>=left;i--){//
               System.out.print(a[high][i]+" ");
           }
           high--;
           for(int i=high;i>=low;i--){//
               System.out.print(a[i][left]+" ");
           }
            left++;

       }

    }