【C++】【记录自己的自学过程】对容器的简单操作以及处理，push_back，copy，transform，insert，erase....

C++
Primer Plus(第六版) 中文版
教材案例，自定义编程练习。


-------------------------------------------------------源代码------------------------------------------------------

#include<iostream>
#include<string>
#include<map>
#include<vector>
#include<iterator>
#include<set>
#include<cctype>
#include<ctime>
#include<algorithm>
std::string& ToLower(std::string& s) { for (int i = 0; i < s.size(); i++) { s[i] = std::tolower(s[i]); }return s; }
int main()
{
	using std::cout;
	using std::endl;
	using std::cin;
	std::srand(time(0));
	std::vector<std::string>words;
	std::string temp;
	int sum = 1;
	cout << "初始化words容器,输入(quit to quit).\n";
	while (cin >> temp && temp != "quit")
		words.push_back(temp);
	cout << "输入的数据容为;.\n";
	std::copy(words.begin(), words.end(), std::ostream_iterator<std::string, char>(cout, " "));
	cout << endl;
	std::set<std::string>wordset;
	std::transform(words.begin(), words.end(), std::insert_iterator < std::set < std::string>>(wordset, wordset.begin()), ToLower);
	cout << "处理后容器中的数组内容为; .\n";
	std::copy(wordset.begin(), wordset.end(), std::ostream_iterator<std::string, char>(cout, " "));
	cout << endl << endl;

	std::map<std::string, int>wordmap;
	for (std::set<std::string>::iterator pr = wordset.begin(); pr != wordset.end(); ++pr)
		wordmap.insert(std::pair<std::string, int>(*pr, std::count(words.begin(), words.end(), *pr)));
	cout << "容器中的键   值.\n";
	for (std::map<std::string, int>::iterator pr = wordmap.begin(); pr != wordmap.end(); ++pr)
	{
		std::pair<std::string, int>temp(pr->first, pr->second);
		cout << temp.first << "\t" << temp.second << endl;
	}
    sort(words.begin(), words.end());
	std::vector<std::string>::iterator pr = unique(words.begin(), words.end());
	words.erase(pr, words.end());
	cout << "words容器的排序所有组合有.\n";
	while (std::next_permutation(words.begin(), words.end()))
	{
		std::copy(words.begin(), words.end(), std::ostream_iterator<std::string, char>(cout, " "));
		cout << endl;
		sum += 1;
	}
	cout << "共有" << sum << "种排序组合方式.\n";
	std::unique(words.begin(), words.end());
	cout << "现在在容器种随机删除一个键值.\n";
	std::string jian = words[rand() % words.size()];
	std::vector<std::string>::iterator last = remove(words.begin(), words.end(), jian);
	words.erase(last, words.end());
	wordset.erase(jian);
	wordmap.erase(jian);
	cout << "现在再次查看三种容器.\n"
		<< "vector<string>; ";
	std::copy(words.begin(), words.end(), std::ostream_iterator<std::string, char>(cout, " "));
	cout << endl << "set<string>; ";
	std::copy(wordset.begin(), wordset.end(), std::ostream_iterator<std::string,char>(cout, " "));
	cout << endl << "map<string,int>;\n";
	for (std::set<std::string>::iterator pr = wordset.begin(); pr != wordset.end(); ++pr)
	{
		cout << *pr << "\t" << wordmap[*pr] << endl;
	}
	cin.get();
	return false;
}