#include <iostream>
#include <vector>
#include <algorithm>
 
struct A{
    int a;
    A(): a(0){}
 
    void operator()(int i) {
        if(i)   a++;
        std::cout << "a:" << a << "  @" << &a << std::endl;
    }
};
 
int main(int argc, char *argv[]) {
    //test data
    std::vector<int> vec;
    vec.push_back(1);
    vec.push_back(1);
    vec.push_back(0);
 
    //accumulator
    A accum;
 
    std::for_each(vec.begin(), vec.end(), accum);
    std::cout << "non-zero elements:" << accum.a << "  @" << &accum.a << std::endl;
 
    return 0;
}

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