#include <iostream>
#include <graphics.h>
#include <cmath>

using namespace std;

int main() {
    int gd = DETECT, gm;
    initgraph(&gd, &gm, "");

    line(100, 400, 400, 400);
    line(100, 400, 100, 100);

    const double k1 = 2, b1 = 1;
    const double k2 = -1, b2 = 3;
    const double k3 = 0.5, b3 = -2;
    const double k4 = -3, b4 = -4;

    for (int x = 100; x <= 400; x++) {
        int y1 = k1 * (x - 100) + b1 + 400;
        putpixel(x, y1, GREEN);

        int y2 = k2 * (x - 100) + b2 + 400;
        putpixel(x, y2, BLUE);

        int y3 = k3 * (x - 100) + b3 + 400;
        putpixel(x, y3, RED);

        int y4 = k4 * (x - 100) + b4 + 400;
        putpixel(x, y4, YELLOW);
    }
    getch();
    closegraph();

    return 0;
}