java - 用于创建二维数组的语法(Syntax for creating a two-dimensional array)

Question

Consider:

(考虑：)

int[][] multD = new int[5][];
multD[0] = new int[10];

Is this how you create a two-dimensional array with 5 rows and 10 columns?

(这是如何创建具有5行10列的二维数组吗？)

I saw this code online, but the syntax didn't make sense.

(我在网上看到了这段代码，但是语法没有意义。)

  ask by AppSensei translate from so

Answer 1

Try the following:

(请尝试以下操作：)

int[][] multi = new int[5][10];

... which is a short hand for something like this:

(...这是类似这样的缩写：)

int[][] multi = new int[5][];
multi[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];

Note that every element will be initialized to the default value for int , 0 , so the above are also equivalent to:

(请注意，每个元素都将初始化为int ， 0的默认值，因此上述内容也等同于：)

int[][] multi = new int[][]{
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};