两数交换不借助第三变量

#include <stdio.h> void swap(int *x, int *y) { *y = *x ^ *y; *x = *x ^ *y; *y = *x ^ *y; } void revert(int *a, int len) { int first = 0, last = len - 1; for (;first < last; first++, last--) swap(&a[first], &a[last]); } int main() { int i, a[] = {1 ,2, 3, 4, 5}; revert(a, 5); for (i = 0; i < 5; i++) printf("%2d", a[i]); getch(); }