请问：为什么delete的时候出问题了？

[isaxu]

#include<stdafx.h>
#include<iostream.h>

char * strcpy(char* dest,const char* source);

void main()
{
char* a = new char;
cout<<"input a:"<<endl;
cin>>a;
char* b = new char;
cout<<"the end is "<<strcpy(b,a);
cout<<"after copy, a is:"<<a<<endl;
cout<<"after copy, b is:"<<b<<endl;
delete b; //如果加上这两个delete，就会出错，可是，书上不是说要释放空间嘛？
delete a;
}

char * strcpy(char* dest,const char* source)
{
char *tmp = new char;
tmp = dest;
while((*source)!='\0')
{
*dest = *source;
source++;
dest++;
}
dest = tmp;
cout<<"dest is "<<dest<<endl;
return dest;
}

[glassshark]

#include<stdafx.h>
#include<iostream.h>

char * strcpy(char* dest,const char* source);

void main()
{
char* a = new char[100];
cout<<"input a:"<<endl;
cin>>a;
char* b = new char[100];
cout<<"the end is "<<strcpy(b,a);
cout<<"after copy, a is:"<<a<<endl;
cout<<"after copy, b is:"<<b<<endl;
delete b; //如果加上这两个delete，就会出错，可是，书上不是说要释放空间嘛？
delete a;
}

char * strcpy(char* dest,const char* source)
{
char *tmp=dest;
while(*dest++=*source++)
return tmp;
}

[glassshark]

#include<stdafx.h>
#include<iostream.h>

char * strcpy(char* dest,const char* source);

void main()
{
char* a = new char[100];
cout<<"input a:"<<endl;
cin>>a;
char* b = new char[100];
cout<<"the end is "<<strcpy(b,a);
cout<<"after copy, a is:"<<a<<endl;
cout<<"after copy, b is:"<<b<<endl;
delete b; //如果加上这两个delete，就会出错，可是，书上不是说要释放空间嘛？
delete a;
}

char * strcpy(char* dest,const char* source)
{
char *tmp=dest;
while(*dest++=*source++);
return tmp;
}

[Cybergate]

接上面的补充一下：

delete[] b;
delete[] a;

[point_to]

#include "stdafx.h"
#include <iostream>
using namespace std;


char * strccpy(char* dest,const char* source);

void main()
{
char* a = new char[10];//要比较的不是一个char 下同！
cout<<"input a:"<<endl;
cin>>a;
char* b = new char[10];
cout<<"the end is "<<strcpy(b,a);
cout<<"after copy, a is:"<<a<<endl;
cout<<"after copy, b is:"<<b<<endl;
delete []b; //如果加上这两个delete，就会出错，可是，书上不是说要释放空间嘛？
delete []a;
}

char * strccpy(char* dest,const char* source)
{
char *tmp = new char;
tmp = dest;
while((*source)!='\0')
{
*dest = *source;
source++;
dest++;
}
dest = tmp;
cout<<"dest is "<<dest<<endl;
return dest;
}

[hdqqq]

我这里测试的结果是内存overrun，就是说发生内存溢出，可能光new一个char是不够的，需要new char[10],然后delete [] a,删除内存使用，另外，在strcpy中有内存泄漏。

[point_to]

不要定义成strcpy()，因为这是保留函数（所以改成乐strccpy）
已经有了这样一个标准函数乐，意思就是这个样子的。

[isaxu]

还是以前的程序，把两条delete语句注释掉，就可以通过了
如果改成 delete [] a;delete [] b; 还是会出现debug error!的windows报错阿～

[hfqian]

#include<stdafx.h>
#include<iostream.h>

char * strcpy(char* dest,const char* source);

void main()
{
char* a = new char[100];
cout<<"input a:"<<endl;
cin>>a;
char* b = new char[100];
cout<<"the end is "<<strcpy(b,a);
cout<<"after copy, a is:"<<a<<endl;
cout<<"after copy, b is:"<<b<<endl;
delete []b;
delete []a;
}

char * strcpy(char* dest,const char* source)
{
char *tmp=dest;
while(*dest++=*source++);
return tmp;
}
本程序已经在VC6.0上测试过了，no problem！


在函数
char * strccpy(char* dest,const char* source)
{
...
}
中，再次分配内存会出现内存泄漏。