概述
list
/*
* array.cpp
*
* Created on: 2014-3-21
* Author: Administrator
*/
#include <iostream>
#include <vector>
#include <deque>
#include <list>
#include <cstdlib>
using namespace std;
// compare only integral part:
bool mycomparison(double first, double second) {
return (int(first) > int(second));
}
void displayList(std::list<double> first) {
std::cout << "displayList:";
for (std::list<double>::iterator it = first.begin(); it != first.end();
++it)
std::cout << ' ' << *it;
std::cout << '\n';
}
int merge() {
std::list<double> first, second;
first.push_back(3.1);
first.push_back(2.2);
first.push_back(2.9);
second.push_back(3.7);
second.push_back(7.1);
second.push_back(1.4);
displayList(first);
displayList(second);
first.sort();
second.sort();
displayList(first);
displayList(second);
first.merge(second);
displayList(first);
displayList(second);
// (second is now empty)
second.push_back(2.1);
first.merge(second,mycomparison); //2.1 1.4 2.2 2.9 3.1 3.7 7.1
displayList(first);
//引數要求明明是個模板類為什麼傳方法也可以呢
first.sort(mycomparison);
displayList(first);
return 0;
// displayList: 3.1 2.2 2.9
// displayList: 3.7 7.1 1.4
// displayList: 2.2 2.9 3.1
// displayList: 1.4 3.7 7.1
// displayList: 1.4 2.2 2.9 3.1 3.7 7.1 結果是排序的
// displayList:
// displayList: 1.4 2.2 2.9 2.1 3.1 3.7 7.1 結果是沒排序的
}
void push() {
list<int> list1(2, 1);
cout << list1.size() << endl;
list1.insert(list1.begin(), 10);
list1.push_back(2);
list1.push_back(3);
list1.push_back(4);
for (list<int>::iterator iter = list1.begin(); iter != list1.end();
iter++) {
cout << *iter << endl;
}
cout << list1.size() << endl;
cout << list1.max_size() << endl;
}
int assign() //分配新的內容到列表容器，取代它的當前內容，並相應地修改其大小。
{
std::list<int> first;
std::list<int> second;
first.assign(7, 100); // 7 ints with value 100
second.assign(first.begin(), first.end()); // a copy of first
int myints[] = { 1776, 7, 4 };
first.assign(myints, myints + 3); // assigning from array
std::cout << "Size of first: " << int(first.size()) << '\n';
std::cout << "Size of second: " << int(second.size()) << '\n';
return 0;
}
int splice ()// 拼接；
{
std::list<int> mylist1, mylist2;
std::list<int>::iterator it;
// set some initial values:
for (int i=1; i<=4; ++i)
mylist1.push_back(i); // mylist1: 1 2 3 4
for (int i=1; i<=3; ++i)
mylist2.push_back(i*10); // mylist2: 10 20 30
it = mylist1.begin();
++it; // points to 2
mylist1.splice (it, mylist2); // mylist1: 1 10 20 30 2 3 4
// mylist2 (empty)
// "it" still points to 2 (the 5th element)
mylist2.splice (mylist2.begin(),mylist1, it);
// mylist1: 1 10 20 30 3 4
// mylist2: 2
// "it" is now invalid.
it = mylist1.begin();
std::advance(it,3); // "it" points now to 30
mylist1.splice ( mylist1.begin(), mylist1, it, mylist1.end());
// mylist1: 30 3 4 1 10 20
std::cout << "mylist1 contains:";
for (it=mylist1.begin(); it!=mylist1.end(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
std::cout << "mylist2 contains:";
for (it=mylist2.begin(); it!=mylist2.end(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
return 0;
}
int main_list() {
// push();
// merge();
// assign();
splice();
return 0;
}
set
/*
* set.cpp
*
* Created on: 2014-3-22
* Author: Administrator
*/
// set::insert (C++98)
#include <iostream>
#include <set>
void displaySet(std::set<int> myset) {
std::cout << "myset contains:";
for (std::set<int>::iterator it = myset.begin(); it != myset.end(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
}
int get_allocator() {
std::set<int> myset;
int * p;
unsigned int i;
// allocate an array of 5 elements using myset's allocator:
//get_allocator 實際返回的是 class allocator
p = myset.get_allocator().allocate(5);
// assign some values to array
for (i = 0; i < 5; i++)
p[i] = (i + 1) * 10;
std::cout << "The allocated array contains:";
for (i = 0; i < 5; i++)
std::cout << ' ' << p[i];
std::cout << '\n';
displaySet(myset);
myset.get_allocator().deallocate(p, 5);
displaySet(myset);
return 0;
}
void insert() {
std::set<int> myset;
std::set<int>::iterator it;
std::pair<std::set<int>::iterator, bool> ret;
// set some initial values:
for (int i = 1; i <= 5; ++i)
myset.insert(i * 10); // set: 10 20 30 40 50
ret = myset.insert(20); // no new element inserted
if (ret.second == false)
it = ret.first; // "it" now points to element 20
myset.insert(it, 25); // max efficiency inserting
myset.insert(it, 24); // max efficiency inserting
myset.insert(it, 26); // no max efficiency inserting
int myints[] = { 5, 10, 15 }; // 10 already in set, not inserted
myset.insert(myints, myints + 3);
displaySet(myset);
}
int key_comp() {
std::set<int> myset;
int highest;
std::set<int>::key_compare mycomp = myset.key_comp();
for (int i = 0; i <= 5; i++)
myset.insert(i * 10);
std::cout << "myset contains:";
highest = *myset.rbegin();
std::cout << highest << std::endl;
std::set<int>::iterator it = myset.begin();
do {
std::cout << ' ' << *it;
} while (mycomp(*(++it), highest));
//myset.key_comp() 通過的是_Compare，_Compare是 struct less 的別名，less過載了（）操作符
//方法內部因沒有訪問內部的私有成員，所有不必用友元的方式，
//總之就是比較大小，引數1<引數2返回真
// typedef _Compare key_compare;
// typename _Compare = std::less<_Key>,
// struct less : public binary_function<_Tp, _Tp, bool>
// {
// bool
// operator()(const _Tp& __x, const _Tp& __y) const
// { return __x < __y; }
// };
std::cout << '\n';
return 0;
}
int main_set() {
// insert();
// key_comp();
get_allocator();
return 0;
}
map
/*
* map.cpp
*
* Created on: 2014-3-22
* Author: Administrator
*/
#include <iostream>
#include <map>
bool fncomp (char lhs, char rhs) {return lhs<rhs;}
struct classcomp {
bool operator() (const char& lhs, const char& rhs) const
{return lhs<rhs;}
};
void map1() {
std::map<char, int> first;
first['a'] = 10;
first['b'] = 30;
first['c'] = 50;
first['d'] = 70;
std::map<char, int> second(first.begin(), first.end());
std::map<char, int> third(second);
std::map<char, int, classcomp> fourth; // class as Compare
bool (*fn_pt)(char, char) = fncomp;
std::map<char, int, bool (*)(char, char)> fifth(fn_pt); // function pointer as Compare
}
int main ()
{
map1();
return 0;
}