我如何给一个二维数组的第二个槽“无限空间”？Java

Question

    int[][] arr3 = new int [arr1.length+arr2.length][];
    for(int i = 0; i<arr1.length; i = i + 1)
    {
        for(int j = 0; j<arr1[i].length; j = j + 1)
        {
            arr3[i][j] = arr1[i][j];
        }
    }
    for (int i2 = 0; i2< arr2.length; i2 = i2 + 1)
    {
        for (int j2 = 0; j2<arr2[i2].length; j2 = j2 + 1)
        {
            arr3[i2+arr1.length][j2] = arr2[i2][j2];
        }
    }
    return arr3;
}

Answer 1

当您执行此操作时：

int [][] y = new int[10][];

然后必须为要使用的区域分配一个常规数组。

y[0] = new int[20];
y[1] = new int[12];

等等。