二维数组
二维数组的每一个元素都是一个一维数组
二维数组的声明
int [] [] a = { {1,2,3},{3,4,5},{4,5,6}};
二维数组的定义
int [] [] a = new int [3] [3];
int [] [] a = new int [3] [];//创建一个长度为3的二维数组,其中每一个一维数组值为空
int[][] b = new int[3][];
b[0] = new int[5];
b[1] = new int[4];
b[2] = new int[]{
1, 5, 9};
System.out.println(Arrays.toString(b[0]));
System.out.println(Arrays.toString(b[1]));
System.out.println(Arrays.toString(b[2]));
运行结果:
[0, 0, 0, 0, 0]
[0, 0, 0, 0]
[1, 5, 9]
int[][] c = new int[][]{
{
1, 2, 3}, {
4, 5, 6}, {
7, 8, 9}};
for (int i = 0; i < c.length; i++) {
for (int j = 0; j < c[i].length; j++) {
System.out.print(c[i][j] + "\t");
}
System.out.println();
}
int[][] d = {
{
1, 2, 3}, {
4, 5, 6}, {
7, 8, 9}};
for (int i = 0; i < d.length; i++) {
System.out.println(Arrays.toString(d[i]));
}
运行结果:
1 2 3
4 5 6
7 8 9
[1, 2, 3]
[4, 5, 6]
[7, 8, 9]