ukui-search/libchinese-segmentation/cppjieba/limonp/LocalVector.hpp

143 lines
2.8 KiB
C++

#ifndef LIMONP_LOCAL_VECTOR_HPP
#define LIMONP_LOCAL_VECTOR_HPP
#include <iostream>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
namespace limonp {
using namespace std;
/*
* LocalVector<T> : T must be primitive type (char , int, size_t), if T is struct or class, LocalVector<T> may be dangerous..
* LocalVector<T> is simple and not well-tested.
*/
const size_t LOCAL_VECTOR_BUFFER_SIZE = 16;
template <class T>
class LocalVector {
public:
typedef const T* const_iterator ;
typedef T value_type;
typedef size_t size_type;
private:
T buffer_[LOCAL_VECTOR_BUFFER_SIZE];
T * ptr_;
size_t size_;
size_t capacity_;
public:
LocalVector() {
init_();
};
LocalVector(const LocalVector<T>& vec) {
init_();
*this = vec;
}
LocalVector(const_iterator begin, const_iterator end) { // TODO: make it faster
init_();
while(begin != end) {
push_back(*begin++);
}
}
LocalVector(size_t size, const T& t) { // TODO: make it faster
init_();
while(size--) {
push_back(t);
}
}
~LocalVector() {
if(ptr_ != buffer_) {
free(ptr_);
}
};
public:
LocalVector<T>& operator = (const LocalVector<T>& vec) {
if(this == &vec){
return *this;
}
clear();
size_ = vec.size();
capacity_ = vec.capacity();
if(vec.buffer_ == vec.ptr_) {
memcpy(buffer_, vec.buffer_, sizeof(T) * size_);
ptr_ = buffer_;
} else {
ptr_ = (T*) malloc(vec.capacity() * sizeof(T));
assert(ptr_);
memcpy(ptr_, vec.ptr_, vec.size() * sizeof(T));
}
return *this;
}
private:
void init_() {
ptr_ = buffer_;
size_ = 0;
capacity_ = LOCAL_VECTOR_BUFFER_SIZE;
}
public:
T& operator [] (size_t i) {
return ptr_[i];
}
const T& operator [] (size_t i) const {
return ptr_[i];
}
void push_back(const T& t) {
if(size_ == capacity_) {
assert(capacity_);
reserve(capacity_ * 2);
}
ptr_[size_ ++ ] = t;
}
void reserve(size_t size) {
if(size <= capacity_) {
return;
}
T * next = (T*)malloc(sizeof(T) * size);
assert(next);
T * old = ptr_;
ptr_ = next;
memcpy(ptr_, old, sizeof(T) * capacity_);
capacity_ = size;
if(old != buffer_) {
free(old);
}
}
bool empty() const {
return 0 == size();
}
size_t size() const {
return size_;
}
size_t capacity() const {
return capacity_;
}
const_iterator begin() const {
return ptr_;
}
const_iterator end() const {
return ptr_ + size_;
}
void clear() {
if(ptr_ != buffer_) {
free(ptr_);
}
init_();
}
};
template <class T>
ostream & operator << (ostream& os, const LocalVector<T>& vec) {
if(vec.empty()) {
return os << "[]";
}
os<<"[\""<<vec[0];
for(size_t i = 1; i < vec.size(); i++) {
os<<"\", \""<<vec[i];
}
os<<"\"]";
return os;
}
}
#endif