1:简单的swap
#include <iostream> using namespace std; class A { public: int x; int getX() { return x; } }; void swap( A & a, A & b ) { int tmp = a.x; a.x = b.x; b.x = tmp; } int main() { A a,b; a.x = 3; b.x = 5; swap(a,b); cout << a.getX() << "," << b.getX(); return 0; }
2:难一点的swap
#include <iostream> using namespace std; void swap( int *& a, int *& b )//指针的引用 { int * tmp = a; a = b; b = tmp; } int main() { int a = 3,b = 5; int * pa = & a; int * pb = & b; swap(pa,pb); cout << *pa << "," << * pb; return 0; }
3:好怪异的返回值
#include <iostream> using namespace std; int & getElement(int * a, int i) { return a[i]; } int main() { int a[] = {1,2,3}; getElement(a,1) = 10; cout << a[1] ; return 0; }
4:神秘的数组初始化
#include <iostream> using namespace std; int main() { int * a[] = {NULL,NULL,new int, new int[6]}; *a[2] = 123; a[3][5] = 456; if(! a[0] ) { cout << * a[2] << "," << a[3][5]; } return 0; } /* 指针数组 a[0]->NULL a[1]-> a[2]->123 a[3]->x,x,x,x,x,456 */