【C++】常用拷贝和替换算法

0.前言

1.copy

#include 
using namespace std;


// 常用拷贝算法 copy
#include
#include

void myPrint(int val)
{
	cout << val << " ";
}

void test01()
{
	vector<int>v;
	for (int i = 0; i < 10; i++)
	{
		v.push_back(i);
	}

	vector<int>v2;
	v2.resize(v.size());
	copy(v.begin(), v.end(), v2.begin());

	for_each(v2.begin(), v2.end(), myPrint);
	cout << endl;
}

int main()
{
	test01();
	cout << "------------------------" << endl;
	//test02();
	//cout << "------------------------" << endl << endl;
	//test03();

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

2.replace

#include 
using namespace std;


// 常用替换算法 replace
#include
#include

class myPrint
{
public:
	void operator()(int val)
	{
		cout << val << " ";
	}
};

void myPrint2(int val)
{
	cout << val << " ";
}

void test01()
{
	vector<int>v;
	
	v.push_back(10);
	v.push_back(20);
	v.push_back(30);
	v.push_back(20);

	cout << "替换前：" << endl;
	for_each(v.begin(), v.end(), myPrint());
	cout << endl;

	//将 20 替换为 2000
	replace(v.begin(), v.end(), 20, 2000);

	for_each(v.begin(), v.end(), myPrint2);
	cout << endl;
}

int main()
{
	test01();
	cout << "------------------------" << endl;
	//test02();
	//cout << "------------------------" << endl << endl;
	//test03();

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

3.replace_if

#include 
using namespace std;


// 常用替换算法 replace_if
#include
#include

class myPrint
{
public:
	void operator()(int val)
	{
		cout << val << " ";
	}
};

bool Greater20(int val)
{
	return val > 20;
}

void test01()
{
	vector<int>v;
	v.push_back(10);
	v.push_back(20);
	v.push_back(30);

	cout << "替换前：" << endl;
	for_each(v.begin(), v.end(), myPrint());
	cout << endl;

	replace_if(v.begin(), v.end(), Greater20, 3000);
	for_each(v.begin(), v.end(), myPrint());
	cout << endl;
}

int main()
{
	test01();
	cout << "------------------------" << endl;
	//test02();
	//cout << "------------------------" << endl << endl;
	//test03();

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

4.swap

#include 
using namespace std;


// 常用替换算法 swap
#include
#include

void myPrint(int val)
{
	cout << val << " ";
}

void test01()
{
	vector<int>v1;
	vector<int>v2;

	for (int i = 0; i < 10; i++)
	{
		v1.push_back(i);
		v2.push_back(i + 100);
	}

	cout << "交换前：" << endl;
	for_each(v1.begin(), v1.end(), myPrint);
	cout << endl;
	for_each(v2.begin(), v2.end(), myPrint);
	cout << endl;

	swap(v1, v2);

	cout << "交换后：" << endl;
	for_each(v1.begin(), v1.end(), myPrint);
	cout << endl;
	for_each(v2.begin(), v2.end(), myPrint);
	cout << endl;
}

int main()
{
	test01();
	cout << "------------------------" << endl;
	//test02();
	//cout << "------------------------" << endl << endl;
	//test03();

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