1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
| #include <bits/stdc++.h>
using namespace std;
#define int long long
template <typename T>
class Vector {
T* _data;
size_t _size;
size_t _capacity;
void expand() {
size_t new_capacity = (_capacity == 0) ? 1 : _capacity * 2;
T* new_data = new T[new_capacity];
for (size_t i = 0; i < _size; i++) new_data[i] = _data[i];
if (_data) delete[] _data;
_data = new_data;
_capacity = new_capacity;
cout << "容量拓展到" << _capacity << '\n';
}
public:
Vector() : _data(nullptr), _size(0), _capacity(0) {}
~Vector() {
if (_data) {
delete[] _data;
_data = nullptr;
}
}
void push_back(const T& value) {
if (_size == _capacity) {
expand();
}
_data[_size] = value;
_size++;
}
T& operator[](size_t index) { return _data[index]; }
size_t size() const { return _size; }
size_t capacity() const { return _capacity; }
};
void solve() {
Vector<int> v;
for (int i = 0; i < 6; i++) {
v.push_back(i);
cout << "插入" << i << ",size:" << v.size() << "\n";
}
}
signed main() {
solve();
return 0;
}
|