交换两个数字的方法

public class SwapTest { static class Pair<F, S> { public F first; public S second; public Pair(F first, S second) { this.first = first; this.second = second; } @Override public String toString() { return "Pair{" + String.valueOf(first) + " " + String.valueOf(second) + "}"; } } /** * 1. 临时变量 */ public static void swap1(Pair<Integer, Integer> pair) { int tmp = pair.first; pair.first = pair.second; pair.second = tmp; } /** * 2. 算数运算法 */ public static void swap2(Pair<Integer, Integer> pair) { pair.first = pair.first - pair.second; pair.second = pair.first + pair.second; pair.first = pair.second - pair.first; } /** * 3. 位运算 */ public static void swap3(Pair<Integer, Integer> pair) { pair.first = pair.first ^ pair.second; pair.second = pair.first ^ pair.second; pair.first = pair.first ^ pair.second; } public static void main(String[] args) { Pair<Integer, Integer> p1 = new Pair<>(1, 2); Pair<Integer, Integer> p2 = new Pair<>(3, 4); Pair<Integer, Integer> p3 = new Pair<>(5, 6); swap1(p1); swap2(p2); swap3(p3); System.out.println(p1); System.out.println(p2); System.out.println(p3); } }