String proplem!!!!Please help

[AvDav]

Bad strrev()

void mystring::strrev()
{
	char c;
	size_t half=len/2, i=0;
	for( ; i<half; ++i)
	{
		c=s[i];
		s[i]=s[len-i-1];
		s[len-i-1]=c;
	}
}