二维数组怎么删除元素java

int[][] arr = {
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

// 删除第一行
int[][] newArr = Arrays.copyOfRange(arr, 1, arr.length);

int[][] arr = {
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

// 删除第一行
int[][] newArr = new int[arr.length - 1][arr[0].length];
System.arraycopy(arr, 1, newArr, 0, arr.length - 1);

import com.google.common.collect.ImmutableListMultimap;

int[][] arr = {
    {1, 2, 3},
    {4, 5, 6},
    {7, 8, 9}
};

// 使用 ImmutableListMultimap 转换数组
ImmutableListMultimap<Integer, Integer> map = ImmutableListMultimap.copyOf(arr);

// 删除第一行
map = map.removeAll(0);

// 转换回二维数组
int[][] newArr = new int[map.size()][map.get(0).size()];
int row = 0;
for (Map.Entry<Integer, Collection<Integer>> entry : map.asMap().entrySet()) {
    int[] values = new int[entry.getValue().size()];
    int col = 0;
    for (Integer value : entry.getValue()) {
        values[col++] = value;
    }
    newArr[row++] = values;
}