#include <cstdlib>
#include <iostream>
#include <cstring>
 
 
char* my_strcpy( char* arr_out,  char* arr_in, int bloc )
{
 char* pc= arr_out;
 
 for(size_t i=0;i<bloc;++i)     
 {
 
        *arr_out++ = *arr_in++ ;
 }
 
 *arr_out = '\0';
 return pc;
}
 
int main()
{
    char * out= new char[20];
    my_strcpy(out,"12345aa\\0aaaaa  AA",20);
    std::cout<<"output data: "<< out << std::endl;
    std::cout<< "the length of my output data: " << strlen(out)<<std::endl;
    system("pause");
    return 0;
}

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