练习题及答案6.pdf

1、 #include iostream.h class M { int x,y; public: M(){x=y=0;} M(int i,int j){x=i;y=j;} void setxy(int i,int j){x=i;y=j;} void copy(M*m); void print(){coutx yendl;} }; void M::copy(M *m){x=m-x;y=m-y;} void fun(M mp, M *m,M mr) { mp.setxy(10,20); m-setxy(10,20); mr.setxy(3,9); } void main() { M mp(1,2),mq(3,4),mr; mr.copy(mp);mr.print(); fun(mp,mq,mr); mp.print(); mq.print(); mr.print(); } 答案： 1 2 1 2 10 20 3 9 2、#include iostream.h class A{ public: A(int m=0){x=m;coutconstructing A xendl;}; virtual ~A(){coutdeltet class A\n;} private: int x; }; class B:public A{ public: B(int n,int m):A(m){size=n;buf=new char[n];coutconstructing B sizeendl;}; ~B(){delete[] buf;coutdelete class B\n;} private: char *buf; int size; }; void main() { B b1(0,3); A *a=new B(10,7); fun(a); } 答案： constructing A 3 constructing B 0 constructing A 7 constructing B 10 delete class B delete class A delete class B delete class A 3、#include iostream.h void main() { char *str[]={Gain,watch,basketball,foot,agenda}; char **p[]={str+2,str,str+3,str+1,str+4}; char ***pp=p; cout*pp[2]; cout(**pp+6); cout(*++*++pp+3); coutpp[0][-1]+2; cout*pp[3]+5; } 答案：footballchina 4、#include iostream.h class F{ private: int *a;int n; void sort(int *a,int n); void swap(int *low,int *high); public: F(int *a1,int n1):a(a1),n(n1){} void sort1(){sort(a,n);} }; void F::sort(int *a,int n) { if(n==1) return; int max_i=0; int max_val=*a; for(int i=0;in;i++) if(a[i]max_val){max_val=a[i];max_i=i;} swap(a[max_i],a+n-1); swap(a,a+n-1); sort(a+1,n-1); } void F::swap(int *low,int *high) { int temp; while(lowhigh)