定义一个string型二维数组，自己赋值，遍历并输出结果

a ab adfdf
adad aoi
akj da ea a
ya
输出如上的n行m列的矩阵

到底是String还是Double呀

public static void main(String[] args) {
       String a[][] = {{"a","b","c"},{"a","b","c"},{"a","b","c"}};


       for(int i = 0;i<a.length;i++){
           for (int j=0;j<a[i].length;j++){
               System.out.print(a[i][j]+" ");
           }
           System.out.println();
       }
    }