翻译在线发音:c++ 交换字符串问题

/*
你定义的那两个ab,bp，这里ab的长度小于bp的，所以在strcpy(x,y)时出现错误～同时strcpy(y,temp)也一样～bp的长度小于temp所以不行.
*/
#include<iostream.h>
#include<string.h>

void swap(char *x,char *y)
{
char temp[20];
strcpy(temp,x);
strcpy(x,y);
strcpy(y,temp);
}

void main()
{

char ap[20]="hello";
char bp[20]="how are you?";
cout<<"ap:"<<ap<<endl;
cout<<"bp:"<<bp<<endl;
swap(ap,bp);
cout<<"swap ap,bp"<<endl;
cout<<"ap:"<<ap<<endl;
cout<<"bp:"<<bp<<endl;
}

void swap(char *x,char *y)
{
char temp;
while(*x!=''||*y!='')
{

temp=*x;
*x=*y;
*y=temp;
x++;
y++;
}
}
main()
{
char a[20] = "hello";
char b[20] = "how are you?";
char *ap=&a;
char *bp;
ap=&a;
bp=&b;

cout<<"ap:"
while(*ap!=''){
cout<<*ap;
ap++;
}
cout<<endl;
cout<<"bp:";
while(*bp!=''){
cout<<*bp;
bp++;
}
cout<<endl;
swap(ap,bp);
while(*ap!='')
{
printf("%c",*ap);
ap++;}

cout<<"ap:"
while(*ap!=''){
cout<<*ap;
ap++;
}
cout<<endl;
cout<<"bp:";
while(*bp!=''){
cout<<*bp;
bp++;
}
cout<<endl;