#include<iostream>
#include<math.h>
#include <stdio.h>
#include <time.h>
#include<chrono>
using namespace std;
#define PI 3.14159265
class DFT_Coeff {
public:
    double real, img;
    DFT_Coeff() {
        real = 0.0;
        img = 0.0;
    }
};
int main(int argc, char** argv)
{
    auto begin = std::chrono::steady_clock::now();
    const int M = 10;
    cout << "Enter the coefficient of simple linear function:\n";
    cout << "ax + by = c\n";
    double a, b, c;
    cin >> a >> b >> c;
    double function[M];
    for (int i = 0; i < M; i++) {
        function[i] = (((a * (double)i) + (b * (double)i)) - c);
        //System.out.print( " "+function[i] + " ");
    }
    cout << "Enter the max K value: ";
    const int k=10;
    double cosine[M];
    double sine[M];
    for (int i = 0; i < M; i++) {
        cosine[i] = cos((2 * i * k * PI) / M);
        sine[i] = sin((2 * i * k * PI) / M);
    }
    DFT_Coeff dft_value[k];
    cout << "The coefficients are: "<<endl;
    for (int j = 0; j < k; j++) {
        for (int i = 0; i < M; i++) {
            dft_value[j].real += function[i] * cosine[i];
            dft_value[j].img += function[i] * sine[i];
        }
        cout << "(" << dft_value[j].real << ") - " << "(" << dft_value[j].img << " i)\n";
    }
    getchar();
    auto end = std::chrono::steady_clock::now();

    auto elapsed_ms = std::chrono::duration_cast<std::chrono::milliseconds>(end - begin);
    std::cout << "The time: " << elapsed_ms.count() << " ms\n";
}