两个 int 类型变量 互换数值 （无第三变量）

	/**  同时交换（很巧妙的算法）*/
	public static void main(String[] args) {
		int a = 5;
		int b = 4;
		b = a + 0 * (a = b);
		System.out.println(a + ":" + b);
	}


	/** 亦或 --类似2进制-- （最快的算法）*/
	public static void main(String[] args) {
		int a = 5;
		int b = 4;
		a = a ^ b;
		b = b ^ a;
		a = a ^ b;
		System.out.println(a + ":" + b);
	}


	/**  数值相加减交换法*/
	public static void main(String[] args) {
		int a = 5;
		int b = 4;
		a = a + b;
		b = a - b;
		a = a - b;
		System.out.println(a + ":" + b);
	}


	/** 数值相乘除交换法（不推荐）除数为0时会抛出异常*/
	public static void main(String[] args) {
		int a = 5;
		int b = 4;
		if (a != 0)// 注意：此处a为除数
		{
			a = a * b;
			b = a / b;
			a = a / b;
		} else {
			a = b;
			b = 0;
		}
		System.out.println(a + ":" + b);
	}

//有更妙的算法一起交流