剔除list中相同的结构体数据

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3、使用unique方法去重

// deduplication.cpp : 定义控制台应用程序的入口点。
//
#include <list>
#include <set>
#include <iostream>
#include <algorithm>
#include <vector>
#include <tchar.h>
using namespace std;

struct tagRecentGameItem
{
	std::wstring strGameCode;
	std::wstring strServerID;
	__int64 nTime;
	tagRecentGameItem()
		: strGameCode(L"")
		, strServerID(L"")
		, nTime(0)
	{
	}

	bool operator < (const tagRecentGameItem& right) const
	{
		if (this->nTime > right.nTime)
		{
			return true;
		}
		if (this->nTime == right.nTime)
		{
			//compare函数在>时返回1，<时返回-1，==时返回0  
			return this->strGameCode.compare(right.strGameCode) < 0;
		}
		return false;
	}
	bool operator == (const tagRecentGameItem& right) const
	{
		bool bEqual = false;
		//_tcsicmp不区分大小写，wcscmp区分大小写
		bEqual = ( 0 == _tcsicmp(this->strGameCode.c_str(), right.strGameCode.c_str()) );
		bEqual &= ( 0 == _tcsicmp(this->strServerID.c_str(), right.strServerID.c_str()) );
		return bEqual;
	}
};
//
typedef std::list<tagRecentGameItem> listRecentGame;
typedef std::set<tagRecentGameItem> setRecentGame;
//
listRecentGame m_LocalList;
listRecentGame m_RemoteList;
setRecentGame m_setGames;

//打印结果
void print_result(listRecentGame& items)
{
	listRecentGame::iterator iter = items.begin();
	for (iter; iter!=items.end(); ++iter)
	{
		printf("gameCode: %ls\n", iter->strGameCode.c_str());
	}
	printf("\n");
}
//逐个比较
void deduplication1(listRecentGame& items)
{
	printf("method :deduplication1\n");

	items.sort();//需要重载操作符<
	listRecentGame::iterator itrB = items.begin();
	listRecentGame::iterator itrE = items.end();
	listRecentGame::iterator itr;
	for (itrB; itrB != itrE; ++itrB)
	{
		itr = itrB;
		++itr;
		for(itr; itr != itrE;)
		{
			if (*itr == *itrB)
			{
				items.erase(itr++);
			}
			else
			{
				++itr;
			}
		}
	}

	//打印结果
	print_result(items);
}
//利用set容器特性去重
void deduplication2(listRecentGame& items)
{
	printf("method :deduplication2\n");

	listRecentGame::iterator iter1 = items.begin();
	listRecentGame::iterator iter2 = items.end();
	for (iter1; iter1 != iter2; ++iter1)
	{
		//需要重载操作符<
		m_setGames.insert(*iter1);
	}
	
	//再写回list
	items.clear();
	setRecentGame::iterator pos = m_setGames.begin();
	for (pos; pos!=m_setGames.end(); ++pos)
	{
		items.push_back(*pos);
	}

	//打印结果
	print_result(items);
}
//stl的unique方法去重
void deduplication3(listRecentGame& items)
{
	printf("method :deduplication3\n");

	//unique函数功能是去除相邻的重复元素,注意是相邻,所以必须先使用sort函数。
	items.sort();
	//unique必须重载==操作符
	listRecentGame::iterator new_end = unique(items.begin(), items.end());
	items.erase(new_end, items.end());
	
	//打印结果
	print_result(items);
}
//
int _tmain(int argc, _TCHAR* argv[])
{
	//装载本地记录
	tagRecentGameItem item;
	memset(&item, 0, sizeof(item));
	item.strGameCode = L"abc";
	item.strServerID = L"s31";
	item.nTime = 20160501183417;
	m_LocalList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"bcd";
	item.strServerID = L"s32";
	item.nTime = 20160501183418;
	m_LocalList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"cde";
	item.strServerID = L"s33";
	item.nTime = 20160501183419;
	m_LocalList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"def";
	item.strServerID = L"s34";
	item.nTime = 20160501183420;
	m_RemoteList.push_back(item);

	//装载远程记录
	memset(&item, 0, sizeof(item));
	item.strGameCode = L"abc";
	item.strServerID = L"s31";
	item.nTime = 20160501183417;
	m_RemoteList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"bcd";
	item.strServerID = L"s32";
	item.nTime = 20160501183418;
	m_RemoteList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"cde";
	item.strServerID = L"s33";
	item.nTime = 20160501183419;
	m_RemoteList.push_back(item);

	memset(&item, 0, sizeof(item));
	item.strGameCode = L"def0";
	item.strServerID = L"s34";
	item.nTime = 20160501183420;
	m_RemoteList.push_back(item);

	//合并到一个list
	m_LocalList.insert(m_LocalList.begin(), m_RemoteList.begin(), m_RemoteList.end());	

	deduplication1(m_LocalList);
	deduplication2(m_LocalList);
	deduplication3(m_LocalList);

	system("pause");

	return 0;
}

运行结果：

STL中的排序都是默认使用小于号来排序。因此，在对结构体排序时，我们就需要重载小于号！比如：set容器在执行insert操作时，必须重载操作符<。另外，unique函数功能是去除相邻的重复元素，而在执行unique操作时必须重载操作符==。

剔除list中相同的结构体数据

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原文地址：http://blog.csdn.net/hellokandy/article/details/51333942