STL算法(18)-transform()

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预定义的函数对象

negate<type>() equal_to<type>()

plus<type>() not_equal_to<type>()

minus<type>() less<type>()

multiplies<type>() greater<type>()

divides<type>() less_equal<type>()

modulus<type>() greater_equal<type>()

logical_not<type>() logical_and<type>()

logical_or<type>()

#include<iostream>
#include<algorithm>
#include<vector>
#include<list>
#include<functional>
#include<iterator>

using namespace std;

int main()
{
	vector<int> ivec;
	list<int> ilist;

	for (int i = 1; i <= 9; i++)
		ivec.push_back(i);
	for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
	{
		cout << *iter << ' ';
	}
	cout << endl;
	// negate 取负值  negate  预定义的函数对象
	transform(ivec.begin(), ivec.end(), ivec.begin(), negate<int>());

	for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
	{
		cout << *iter << ' ';
	}
	cout << endl;

	// ilist  做变换的时候必须保证 ilist  有空间
	// back_inserter  加上头文件  #include<iterator>
	transform(ivec.begin(), ivec.end(), back_inserter(ilist),bind2nd(multiplies<int>(), 10));
	for (list<int>::iterator iter = ilist.begin(); iter != ilist.end(); iter++)
	{
		cout << *iter << ' ';
	}
	cout << endl;

	transform(ilist.begin(), ilist.end(), ostream_iterator<int>(cout, " "), negate<int>());
	//
	system("pause");
	return 0;
}

第二种形式  融合数据

#include<iostream>
#include<vector>
#include<list>
#include<algorithm>
//
#include<iterator>
#include<functional>
using namespace std;

int main()
{
	vector<int> ivec;
	list<int> ilist;

	for (int i = 1; i <= 9; i++)
		ivec.push_back(i);
	for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
		cout << *iter << ' ';
	cout << endl;

	transform(ivec.begin(), ivec.end(), ivec.begin(), ivec.begin(), multiplies<int>());

	for (vector<int>::iterator iter = ivec.begin(); iter != ivec.end(); iter++)
		cout << *iter << ' ';
	cout << endl;

	// back_inserter  因为 ilist 是空的，所以我们要用插入迭代器
	transform(ivec.begin(), ivec.end(), ivec.begin(), back_inserter(ilist), plus<int>());

	for (list<int>::iterator iter = ilist.begin(); iter != ilist.end(); iter++)
		cout << *iter << ' ';
	cout << endl;

	transform(ivec.begin(), ivec.end(), ilist.begin(), ostream_iterator<int>(cout, " "), minus<int>());

	//
	system("pause");
	return 0;
}

STL算法(18)-transform()

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原文地址：http://blog.csdn.net/taotaoah/article/details/52237326