BOOST 练习程序（1）
接触BOOST没多久，这是自己目前能想到的解。（可能有更好的解答，还望不吝赐教）题目：
简化以下程序，将函数对象 divide_by 转换为一个函数，并将 for 循环替换为用一个标准的 C++ 算法来输出数据：
#include <algorithm>
#include <functional>
#include <vector>
#include <iostream>
class divide_by
: public std::binary_function<int, int, int>
{
public:
int operator()(int n, int div) const
{
return n / div;
}
};
int main()
{
std::vector<int> numbers;
numbers.push_back(10);
numbers.push_back(20);
numbers.push_back(30);
std::transform(numbers.begin(), numbers.end(), numbers.begin(), std::bind2nd(divide_by(), 2));
for (std::vector<int>::iterator it = numbers.begin(); it != numbers.end(); ++it)
std::cout << *it << std::endl;
}
自己给出的解答:
#include <algorithm>
#include <functional>
#include <vector>
#include <iostream>
#include <boost/function.hpp>
int divide_by(int n, int div)
{
return n / div;
}
void print_1(int num)
{
printf("==%d==\n", num);
}
int main()
{
std::vector<int> numbers;
numbers.push_back(10);
numbers.push_back(20);
numbers.push_back(30);
boost::function<int (int, int)> func_1 = divide_by;
std::transform(numbers.begin(), numbers.end(), numbers.begin(), std::bind2nd(func_1, 2));
std::for_each(numbers.begin(), numbers.end(), print_1);
}
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