example3_parametrized_functor.cpp

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
#include <iostream>
#include <vector>
#include <algorithm>

class DivisibleBy {
private:
    int divisor;

public:
    DivisibleBy(int d) : divisor(d) {}

    bool operator()(int x) const {
        return x % divisor == 0;
    }
};

int main() {
    std::vector<int> numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
    
    int divisor = 3;
    DivisibleBy isDivisibleBy3(divisor);
    
    int count = std::count_if(numbers.begin(), numbers.end(), isDivisibleBy3);
    
    std::cout << "Numbers divisible by " << divisor << ": " << count << std::endl;

    return 0;
}