copyIfSolution

#include <iostream>


//int strlenM(const char* str)
//{
//    int len{ 0 };
//    for (; *str++; ++len);
//    return len;
//}

template <typename T>
void forEach(T* arrB, T* arrE, void(*action)(T& el))
{
    while (arrB != arrE)
    {
        if (action) { action(*arrB++); };
    }
}


void printElement(int& el)
{
    std::cout << el << ' ';
};


template <typename T>
bool trueer(const T& el) { return true; }
template <typename T>
bool falseer(const T& el) { return false; }

template <typename T>
bool evener(const T& el){ return !(el % 2);}
template <typename T>
bool odder(const T& el){ return (el % 2); }

template <typename T>
int copy_if(T* srcB, T* srcE, T* destB, T* destE, bool(*pred)(const T& el))
{
    int copyCount{ 0 };

    while (srcB != srcE and destB != destE)
    {
        if (pred(*srcB))
        {
           *destB++ = *srcB;
            ++copyCount;
        }
        ++srcB;
    }
    return copyCount;
}

//void printArr(int* ptr, int size)
//{
//    for (auto elP{ ptr }; elP != (ptr + size); ++elP)
//    {
//        std::cout << *elP << ' ';
//    }
//    std::cout << '\n';
//}

//template <typename T>
//int copy_if(T* srcB, T* srcE, T* destB, T* destE, bool(*pred)(const T& el))
//{
//    int count{ 0 };
//    for (auto elP{ srcB }; (elP != srcE) && (destB + count != destE); ++elP)
//    {
//        const int& elm{ *elP };
//        if (pred(elm))
//        {
//            *(destB + count) = *elP;
//            ++count;
//        }
//    }
//    return count;
//}

int main()
{
    const int arrSize{ 10 };
    int arr[arrSize]{ 1,2,3,4,5,6,7,8,9,10 };

    int* arrBegin{ arr };
    int* arrEnd{ arr + arrSize };

    const int arr1Size{ 10 };
    int arr1[arr1Size]{};

    int* arr1Begin{ arr1 };
    int* arr1End{ arr1 + arr1Size };

    forEach(arrBegin, arrEnd, printElement);
    std::cout << '\n';
    forEach(arr1Begin, arr1End, printElement);
    std::cout << '\n';
    int copyCount = copy_if(arrBegin+2, arrEnd-2, arr1Begin+2, arr1End-2, evener);
    forEach(arr1Begin, arr1End, printElement);
    std::cout << '\n' << copyCount << " elements copied\n";
    std::cout << '\n';
    //copyCount = copy_if(arrBegin, arrEnd, arr1Begin, arr1End, odder);
    //forEach(arr1Begin, arr1End, printElement);
    //std::cout << '\n' << copyCount << " elements copied\n";
    //std::cout << '\n';

    ////char str[15]{ 'H','e','0','o','!','\0'};
    //int strSize{ 15 };
    //char* string{ new char[strSize] };
    //char str[20]{ "Hello, world!" };
    //int arr[5]{ 1,2,3,4,5 };

    //std::cout << str << ' ' << strlenM(str) << '\n';
    //std::cout << str << ' ' << strlenM(str) << '\n';
}