Java如何交换两个数的值

int a = 2;
int b = 3;
int temp;
temp = a;
a = b;
b = temp;

int a = 4;
int b = 6;
a = a^b;
b = a^b;
a = a^b;

int a = 7;
int b = 9;
a = a+b;
b = a-b;
a = a-b;

public static void main(String[] args) {
    int a = 6;
    int b = 5;
    int arr[] = {a,b};
    swap(arr);
    a = arr[0];
    b = arr[1];
    System.out.println("a: "+a+"ttt"+"b: "+b);
}

private static void swap(int[] arr) {
    int temp = arr[0] ;
    arr[0] = arr[1];
    arr[1] = temp;
}

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