小编Lor*_*ton的帖子

我正在学习如何使用仿函数,所以我创建了一个,我不明白为什么我的计数器变量在程序结束时为0.

这里的代码:

#include"stdafx.h"
#include<iostream>
#include<vector>
#include<algorithm>
#include<map>
#include<list>


using namespace std;

class myFunctor {
public:
    myFunctor():counter(0) {}
    void operator()(int i) { cout << "in the functor: " << i ; counter++; cout << "   counter=" << counter << endl; }
    int getCounter() const { return counter; }
private:
    int counter;
};

int main()
{
    vector<int> v{ 1,2,3,4,5,6,7,8,9,10 };
    myFunctor f;

    for_each(v.begin(), v.end(), f);

    cout << "counter=" << f.getCounter() << endl;

    return 0;
}

结果如下:

in the functor: 1   counter=1
in …