【STL】for_each示例

void myfun1(int& i)
{
std::cout << i << " ";
}

void myfun2(int i, const char* prefix)
{
std::cout << prefix << i << std::endl;
}

struct mystruct1 {
void operator() (int& i)
{
std::cout << i << " ";
}
} myobject1;

struct mystruct2 {
const char* prefix_;
mystruct2(const char* prefix): prefix_(prefix) {}
void operator() (int& i) {
std::cout << prefix_ << i << std::endl;
}
};

class myclass1
{
public:
void operator() (int& i)
{
std::cout << i << " ";
}
};

class myclass2
{
public:
const char* prefix_;
myclass2(const char* prefix): prefix_(prefix){};
void operator() (int& i)
{
std::cout << i << " ";
}
};

void test_for_each()
{
int ar[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
std::vector<int> v(ar, ar + 9);

// 一个参数的普通函数
std::cout << "myfunction1 output below: " << std::endl;
for_each(v.begin(), v.end(), myfun1);
std::cout << std::endl;

// 二个参数的普通函数
std::cout << "myfunction2 output below: " << std::endl;
for_each(v.begin(), v.end(), std::bind2nd(std::ptr_fun(myfun2), "i = "));

// 不带参的结构体
std::cout << "mystruct1 output below: " << std::endl;
for_each(v.begin(), v.end(), mystruct1());
// for_each(v.begin(), v.end(), myobject1); // 这个方法也行.
std::cout << std::endl;

// 带参的结构体
std::cout << "mystruct2 output below: " << std::endl;
for_each(v.begin(), v.end(), mystruct2("i = "));

// 不带参的类
std::cout << "myclass1 output below: " << std::endl;
for_each(v.begin(), v.end(), myclass1());
std::cout << std::endl;

// 带参的类
std::cout << "myclass2 output below: " << std::endl;
for_each(v.begin(), v.end(), myclass2("i = "));
std::cout << std::endl;
}