STL笔记

C++中STL用法超详细总结_list_HUST_Miao-DevPress官方社区

String

1.find 

size_t find (const string& str, size_t pos = 0) const;//注意这里pos是全缺省参数，可修改。 find('.',3);

size_t find (const char* s, size_t pos = 0) const;

size_t find (const char* s, size_t pos, size_t n) const;

size_t find (char c, size_t pos = 0) const;

int main ()
{
  std::string str ("There are two needles in this haystack with needles.");
  std::string str2 ("needle");
  // different member versions of find in the same order as above:
  std::size_t found = str.find(str2);
  if (found!=std::string::npos)
    std::cout << "first 'needle' found at: " << found << '\n'
}

2.c_str 

函数返回值：const char* c_str() const;
c++为了兼容c,提出c_str,c_string是以斜杠零为结束标志，而string不包括斜杠零。char*a = "sdfsdf";转成string，需要用到c_str   string  aa = a.c_str();

This array includes the same sequence of characters that make up the value of the string object plus an additional terminating null-character ('\0') at the end.

3.reverse(str.begin(),str.end());

4.string可以使用迭代器，但是一般使用operate[],vector也常用[],

5.to_string(T )    stoi等

6.istream& getline (istream& is, string& str);

练习：输入“i like china.”,输出“china. like i”

// ConsoleApplication1.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
#include 
#include
#include
using namespace std;
void reverse(string &str)
{
	int end = str.size();
	for (int i = 0; i < str.size() / 2; i++)
	{
		swap(str[i], str[end - 1]);
		end--;
	}
}
int main()
{
	string str;
	string newstr;
	getline(cin, str);
	int end = str.size();
	for (int i = 0; i < str.size()/2; i++)
	{
		swap(str[i], str[end - 1]);
	    end--;
	}
	cout << str;
	
	size_t pos = str.find(' ');
	while (pos <= end)
	{
		string temp = str.substr(0, pos);
		reverse(temp);
		newstr.append(temp+" ");
		str = str.substr(pos+1);
		pos = str.find(' ');
		if (pos == std::string::npos)
		{	
			reverse(str);
			newstr.append(str);
			break;
		}
	}
	
	return 0;
}

List

1.算法库中sort函数只适用于内存连续 Vector,可以先把数据拷贝到vector,sort排序，再拷贝回list;

list有单独的sort