C++博客-patriking-随笔分类-C++ STL

STL 容器Deque

patriking — Fri, 21 Jan 2011 14:25:00 GMT

template <class T, template <class U> class Allocator = allocator>
class deque {
public:
// typedefs:
    typedef iterator;
    typedef const_iterator;
    typedef Allocator<T>::pointer pointer;
    typedef Allocator<T>::reference reference;
    typedef Allocator<T>::const_reference const_reference;
    typedef size_type;
    typedef difference_type;
    typedef T value_type;
    typedef reverse_iterator;
    typedef const_reverse_iterator;
// allocation/deallocation:
    deque();
    deque(size_type n, const T& value = T());
    deque(const deque<T, Allocator>& x);
    template <class InputIterator>
    deque(InputIterator first, InputIterator last);
    ~deque();
    deque<T, Allocator>& operator=(const deque<T, Allocator>& x);
    void swap(deque<T, Allocator>& x);
// accessors:
    iterator begin();
    const_iterator begin() const;
    iterator end();
    const_iterator end() const;
    reverse_iterator rbegin();
    const_reverse_iterator rbegin();
    reverse_iterator rend();
    const_reverse_iterator rend();
    size_type size() const;
    size_type max_size() const;
    bool empty() const;
    reference operator[](size_type n);
    const_reference operator[](size_type n) const;
    reference front();
    const_reference front() const;
    reference back();
    const_reference back() const;
// insert/erase:
    void push_front(const T& x);
    void push_back(const T& x);
    iterator insert(iterator position, const T& x = T());
    void insert (iterator position, size_type n, const T& x);
    template <class InputIterator>
    void insert (iterator position, InputIterator first, InputIterator last);
    void pop_front();
    void pop_back();
    void erase(iterator position);
    void erase(iterator first, iterator last);
};

patriking 2011-01-21 22:25 发表评论

STL 容器List

patriking — Fri, 21 Jan 2011 14:15:00 GMT

template <class T, template <class U>
class Allocator = allocator> class list
{
public:
// typedefs:
    typedef iterator
    typedef const_iterator
    typedef Allocator<T>::pointer pointer
    typedef Allocator<T>::reference reference
    typedef Allocator<T>::const_reference const_reference
    typedef size_type
    typedef difference_type
    typedef T value_type
    typedef reverse_iterator
    typedef const_reverse_iterator;
// allocation/deallocation:
    list()
    list(size_type n, const T& value = T())
    template <class InputIterator>
    list(InputIterator first, InputIterator last)
    list(const list<T, Allocator>& x)
    ~list()
    list<T, Allocator>& operator=(const list<T, Allocator>& x)
    void swap(list<T, Allocator>& x);
// accessors:
    iterator begin()
    const_iterator begin() const
    iterator end()
    const_iterator end() const
    reverse_iterator rbegin()
    const_reverse_iterator rbegin();
    reverse_iterator rend();
    const_reverse_iterator rend();
    bool empty() const;
    size_type size() const;
    size_type max_size() const;
    reference front();
    const_reference front() const;
    reference back();
    const_reference back() const;
// insert/erase:
    void push_front(const T& x);
    void push_back(const T& x);
    iterator insert(iterator position, const T& x = T());
    void insert(iterator position, size_type n, const T& x);
    template <class InputIterator>
    void insert(iterator position, InputIterator first, InputIterator last);
    void pop_front();
    void pop_back();
    void erase(iterator position);
    void erase(iterator first, iterator last);
// special mutative operations on list:
    void splice(iterator position, list<T, Allocator>& x);
    void splice(iterator position, list<T, Allocator>& x, iterator i);
    void splice(iterator position, list<T, Allocator>& x,
    iterator first, iterator last);
    void remove(const T& value);
    template <class Predicate> void remove_if(Predicate pred);
    void unique();
    template <class BinaryPredicate> void unique(BinaryPredicate binary_pr
    void merge(list<T, Allocator>& x);
    template <class Compare> void merge(list<T, Allocator>& x, Compare com
    void reverse();
    void sort();
    template <class Compare> void sort(Compare comp);
};

patriking 2011-01-21 22:15 发表评论

STL 容器Vector

patriking — Wed, 19 Jan 2011 14:22:00 GMT

Vector is a kind of sequence that supports random access iterators. In addition, it supports (amortized) constant time insert and erase operations at the end;
insert and erase in the middle take linear time. Storage management is handled automatically, though hints can be given to improve efficiency.

template <class T, template <class U> class Allocator = allocator>
class vector {
public:
// typedefs:
    typedef iterator;
    typedef const_iterator;
    typedef Allocator::pointer pointer;
    typedef Allocator::reference reference;
    typedef Allocator::const_reference const_reference;
    typedef size_type;
    typedef difference_type;
    typedef T value_type;
    typedef reverse_iterator;
    typedef const_reverse_iterator;
// allocation/deallocation:
    vector();
    vector(size_type n, const T& value = T());
    vector(const vector& x);
    template vector(InputIterator first, InputIterator last);
    ~vector();
    vector& operator=(const vector& x);
    void reserve(size_type n);
    void swap(vector& x);

// accessors:
    iterator begin();
    const_iterator begin() const;
    iterator end();
    const_iterator end() const;
    reverse_iterator rbegin();
    const_reverse_iterator rbegin();
    reverse_iterator rend();
    const_reverse_iterator rend();
    size_type size() const;
    size_type max_size() const;
    size_type capacity() const;
    bool empty() const;
    reference operator[](size_type n);
    const_reference operator[](size_type n) const
    reference front();
    const_reference front() const;
    reference back();
    const_reference back() const;

// insert/erase:
    void push_back(const T& x);
    iterator insert(iterator position, const T& x = T());
    void insert(iterator position, size_type n, const T& x);
    template
    void insert(iterator position, InputIterator first, InputIterator last);
    void pop_back();
    void erase(iterator position);
    void erase(iterator first, iterator last);
};

patriking 2011-01-19 22:22 发表评论

STL之Set operation on sorted structures

patriking — Tue, 18 Jan 2011 02:17:00 GMT

Set operations on sorted structures 为STL中对两个有序序列的操作，包括包含、合并、求交集、求差、求对称差。
包含：如果[first2,last2)包含在[first1,last1)中，返回true,否则返回false。
bool includes(InputIterator1 first1, InputIterator1 last1,InputIterator2 first2, InputIterator2 last2)
bool includes(InputIterator1 first1, InputIterator1 last1,InputIterator2 first2, InputIterator2 last2, Compare comp)

合并：合并[first1,last1)与[first2,last2)两个集合。
OutputIterator set_union(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result)
OutputIterator set_union(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp)

求交集：求[first1,last1)与[first2,last2)两个集合的交集。
OutputIterator set_intersection(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result)
OutputIterator set_intersection(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp)

求差：求在[first1,last1)中，而不在[first2,last2)的元素集合。
OutputIterator set_difference(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result)
OutputIterator set_difference(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp)

求对称差：两个集合之和集减去两个集合之交集。
OutputIterator set_symmetric difference(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result)
OutputIterator set_symmetric difference(InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp)

#include<iostream>
#include<algorithm>
#include<vector>
#include<iterator>
using namespace std;
void init(vector<int>& v, int a, int b)
{
    v.clear();
    for(int i = a; i <= b; i++){
        v.push_back(i);
    }
}
int main()
{
    vector<int>v1, v2;
    vector<int>::iterator itr;
    cout << "Includes operator:" << endl;
    init(v1,1,5);
    init(v2,1,8);
    cout << "Vector v1: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "Vector v2: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "v2 is in v1 ? " << (includes(v1.begin(),v1.end(),v2.begin(),v2.end()) ? "yes" : "no") << endl;
    cout << "v1 is in v2 ? " << (includes(v2.begin(),v2.end(),v1.begin(),v1.end()) ? "yes" : "no") << endl;

    cout << endl;
    init(v1,1,5);
    init(v2,3,8);
    cout << "Vector v1: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "Vector v2: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_union operator on v1,v2: ";
    set_union(v1.begin(),v1.end(),v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;

    init(v1,1,5);
    init(v2,3,8);
    cout << "Vector v1: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "Vector v2: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_intersecion operator on v1,v2: ";
    set_intersection(v1.begin(),v1.end(),v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;

    init(v1,1,5);
    init(v2,3,8);
    cout << "Vector v1: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "Vector v2: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_difference operator, v1 to v2: ";
    set_difference(v1.begin(),v1.end(),v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_difference operator, v2 to v1: ";
    set_difference(v2.begin(),v2.end(),v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;

    init(v1,1,5);
    init(v2,3,8);
    cout << "Vector v1: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "Vector v2: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_symmetric_difference operator, v1 to v2: ";
    set_symmetric_difference(v1.begin(),v1.end(),v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "set_symmetric_difference operator, v2 to v1: ";
    set_symmetric_difference(v2.begin(),v2.end(),v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    return 0;
}

Includes operator:
Vector v1: 1 2 3 4 5
Vector v2: 1 2 3 4 5 6 7 8
v2 is in v1 ? no
v1 is in v2 ? yes

Vector v1: 1 2 3 4 5
Vector v2: 3 4 5 6 7 8
set_union operator on v1,v2: 1 2 3 4 5 6 7 8

Vector v1: 1 2 3 4 5
Vector v2: 3 4 5 6 7 8
set_intersecion operator on v1,v2: 3 4 5

Vector v1: 1 2 3 4 5
Vector v2: 3 4 5 6 7 8
set_difference operator, v1 to v2: 1 2
set_difference operator, v2 to v1: 6 7 8

Vector v1: 1 2 3 4 5
Vector v2: 3 4 5 6 7 8
set_symmetric_difference operator, v1 to v2: 1 2 6 7 8
set_symmetric_difference operator, v2 to v1: 1 2 6 7 8

patriking 2011-01-18 10:17 发表评论

STL之Merge

patriking — Mon, 17 Jan 2011 13:35:00 GMT

STL中合并算法merge介绍，merge与inplace_merge。
merge合并两个有序的sequence，默认为<比较，可自定义比较函数comp，结果保存在[result, result + (last1 - first1) + (last2 - first2)) 中。函数定义如下：
OutputIterator merge (InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result)
OutputIterator merge (InputIterator1 first1, InputIterator1 last1, InputIterator2 first2, InputIterator2 last2, OutputIterator result, Compare comp)

inplace_merge合并一个中前后两段分别有序的序列，即[first,middle)与[middle,last)分别有序，合并这两个子序列，并把结果保存在[first,last）中。
inplace_merge (BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last);
inplace_merge (BidirectionalIterator first, BidirectionalIterator middle, BidirectionalIterator last, Compare comp);

#include<string>
#include<algorithm>
#include<iostream>
#include<iterator>
#include<vector>
using namespace std;
int main()
{
    vector<int>v1;
    vector<int>v2;
    vector<int>v3;
    vector<int>::iterator vecitr;
    for(int i = 1; i <= 10; i++){
        v1.push_back(i%7);
        v2.push_back(i%4);
    }
    sort(v1.begin(),v1.end());
    cout << "Fisrt vecter: ";
    copy(v1.begin(),v1.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    sort(v2.begin(),v2.end());
    cout << "Second vecter: ";
    copy(v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    cout << "Merge this two vecter: ";
    merge(v1.begin(),v1.end(),v2.begin(),v2.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    for(int i = 1; i <= 10; i++){
        v3.push_back(i%7);
    }
    sort(v3.begin(),v3.end());
    int x = v3.size();
    for(int i = 1; i <= 10; i++){
        v3.push_back(i%4);
    }
    vecitr = v3.begin();
    advance(vecitr,x);
    sort(vecitr,v3.end());
    cout << "Third vecter: ";
    copy(v3.begin(),v3.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    cout << "inplace_Merge third vecter: ";
    inplace_merge(v3.begin(),vecitr,v3.end());
    copy(v3.begin(),v3.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;
    return 0;
}

Fisrt vecter: 0 1 1 2 2 3 3 4 5 6

Second vecter: 0 0 1 1 1 2 2 2 3 3

Merge this two vecter: 0 0 0 1 1 1 1 1 2 2 2 2 2 3 3 3 3 4 5 6

Third vecter: 0 1 1 2 2 3 3 4 5 6 0 0 1 1 1 2 2 2 3 3

inplace_Merge third vecter: 0 0 0 1 1 1 1 1 2 2 2 2 2 3 3 3 3 4 5 6

patriking 2011-01-17 21:35 发表评论

STL之Binary search

patriking — Sun, 16 Jan 2011 14:40:00 GMT

STL中对于有序序列（vector,list等）提供了相当相当强大的二分搜索Binary search算法。对于可以随机访问容器（如vector等），binary search负载度为对数级别（LogN)，对于非随机访问容器（如list），则算法复杂度为线性。现在简要介绍一下几种常用的binary search算法：

ForwardIterator lower_bound (ForwardIterator first,ForwardIterator last, const T& value)
ForwardIterator lower_bound (ForwardIterator first,ForwardIterator last, const T& value, Compare comp)
//查找最远的一个iterator i，使得[first,i)里面的任意一个iterator j，有 *j < value or comp(*j,value)==true.

ForwardIterator upper_bound (ForwardIterator first,ForwardIterator last, const T& value)
ForwardIterator upper_bound (ForwardIterator first,ForwardIterator last, const T& value, Compare comp)
//查找最远的一个iterator i，使得[first,i)里面的任意一个iterator j，有 !(*j < value) or comp(*j,value)==false.

pair equal_range(ForwardIterator first, ForwardIterator last, const T& value)
pair equal_range(ForwardIterator first, ForwardIterator last, const T& value, Compare comp)
//查找最大的subrange[i,j)，使得任意一个iterator in [i,j)满足!(*k
bool binary_search (ForwardIterator first, ForwardIterator last, const T& value)
bool binary_search (ForwardIterator first, ForwardIterator last, const T& value, Compare comp)
// 查找是否在[first,last)中存在iterator i,满足 !(*i// 存在则返回true,否则返回false.

#include<algorithm>
#include<iostream>
#include<vector>
#include<iterator>
using namespace std;
int main()
{
    vector<int>v;
    vector<int>::iterator itr;
    pair< vector<int>::iterator, vector<int>::iterator >vecpair;

    for(int i = 1; i <= 20; i++){
        v.push_back(i%6);
    }
    sort(v.begin(),v.end());
    cout << "array: " << endl << "    ";
    copy(v.begin(),v.end(),ostream_iterator<int>(cout," "));
    cout << endl;

    //lower_bound
    cout << "lower_bound function, value = 3:" << endl;
    itr = lower_bound(v.begin(),v.end(),3);
    cout << "    [first, itr) = ";
    copy(v.begin(),itr,ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "    [itr, last) = ";
    copy(itr,v.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;

    // upper_bound
    cout << "upper_bound function, value = 3:" << endl;
    itr = upper_bound(v.begin(),v.end(),3);
    cout << "    [first, itr) = ";
    copy(v.begin(),itr,ostream_iterator<int>(cout," "));
    cout << endl;
    cout << "    [itr, last) = ";
    copy(itr,v.end(),ostream_iterator<int>(cout," "));
    cout << endl << endl;

    // equal_range
    cout << "equal_range function, value = 3:" << endl;
    vecpair = equal_range(v.begin(),v.end(),3);

    cout << "    [vecpair->first, vecpair->second) = ";
    copy(vecpair.first, vecpair.second, ostream_iterator<int>(cout," "));
    cout << endl << endl;

    //binary_search, value = 3
    cout << "binary_search function, value = 3:" << endl;
    cout << "3 is " << (binary_search(v.begin(),v.end(),3) ? "":"not ") << "in array." << endl;
    cout << endl;

    //binary_search, value = 6
    cout << "binary_search function, value = 6:" << endl;
    cout << "6 is " << (binary_search(v.begin(),v.end(),6) ? "":"not ") << "in array." << endl;
    cout << endl;

    return 0;
}

array:
    0 0 0 1 1 1 1 2 2 2 2 3 3 3 4 4 4 5 5 5
lower_bound function, value = 3:
    [first, itr) = 0 0 0 1 1 1 1 2 2 2 2
    [itr, last) = 3 3 3 4 4 4 5 5 5

upper_bound function, value = 3:
    [first, itr) = 0 0 0 1 1 1 1 2 2 2 2 3 3 3
    [itr, last) = 4 4 4 5 5 5

equal_range function, value = 3:
    [vecpair->first, vecpair->second) = 3 3 3

binary_search function, value = 3:
3 is in array.

binary_search function, value = 6:
6 is not in array.

patriking 2011-01-16 22:40 发表评论