Страустрап Бьярн
Шрифт:
case 0: return 1;
case 1: return x;
default: return x*pow(x,n-1);
}
}
void error(char *s)
{
cout ‹‹ s;
}
b1__13.cxx
#include ‹stream.hxx›
// 1.11
class vector {
int *v;
int sz;
public:
vector(int); // constructor
~vector; // destructor
int size { return sz; }
void set_size(int);
int& operator[](int);
int& elem(int i) { return v[i]; }
};
// 1.13
class vec: public vector {
int low, high;
public:
vec(int, int);
int& elem(int);
int& operator[](int);
};
main
{
vector a(10);
for (int i=0; i‹a.size; i++) {
a[i] = i;
cout ‹‹ a[i] ‹‹ " ";
}
cout ‹‹ "\n";
vec b(10,19);
for (i=0; i‹b.size; i++) b[i+10] = a[i];
for (i=0; i‹b.size; i++) cout ‹‹ b[i+10] ‹‹ " ";
cout ‹‹ "\n";
}
extern void exit(int);
// 1.13
void error(char* p)
{
cerr ‹‹ p ‹‹ "\n";
exit (1);
}
// 1.11
vector::vector(int s)
{
if (s‹=0) error("bad vector size");
sz = s;
v = new int[s];
}
int& vector::operator[](int i)
{
if (i‹0 || sz‹=i) error("vector index out of range");
return v[i];
}
vector::~vector
{
delete v;
}
// 1.13
int& vec::elem(int i)
{
return vector::elem(i-low);
}
vec::vec(int lb, int hb): (hb-lb+1)
{
if (hb-lb‹0) hb = lb;
low = lb;
high = hb;
}
void vector::set_size(int) {/* dummy */}
int& vec::operator[](int i)
{
if (i‹low || high‹i) error("vec index out of range");
return elem(i);
}
b1__14.cxx
#include‹stream.hxx›
extern void exit(int);
extern void error(char*);
// 1.11
class vector {
int *v;
int sz;
public:
vector(int); // constructor
~vector; // destructor
int size { return sz; }
void set_size(int);
int& operator[](int);
int& elem(int i) { return v[i]; }
};
vector::vector(int s)
{
if (s‹=0) error("bad vector size");
sz = s;
v = new int[s];
}
int& vector::operator[](int i)