我知道Java总是按值传递,但我不明白为什么这样可行:
public static void swap(int[] arr, int i, int j)
{
int tmp = arr[i];
arr[i] = arr[j];
arr[j] = tmp;
}
public static void main(String[] args)
{
int[] arr = {3, 4, 5, 6};
swap(arr, 1, 3);
// arr becomes {3, 6, 5, 4}
}
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这不起作用:
public static void swap(int[] arr, int[] arr2)
{
int[] tmp = arr;
arr = arr2;
arr2 = tmp;
}
public static void main(String[] args)
{
int[] arr = {3, 4, 5, 6};
int[] …Run Code Online (Sandbox Code Playgroud)