Make circles move to opposing directions after sometime

[avarus]

Hey, I am new in c++ programming and I wanted to write a small game using classes and objects. So my problem is that I would like to make the two 'Enemy' circles 'tp' (top) and 'btm' (bottom) move randomly in the x plane, let's say after every 10 seconds they change direction either from left to right or vice versa INDEPENDENTLY. I know my whole code is not the best or the most efficient but please just bear with me, Thanks in advance.

  #include <iostream>
#include <graphics.h>
#include <dos.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <windows.h>

using namespace std;

class hero {
protected:
    string heroname;
    int heroHP;
    int heroattack;
    int i;
    int j;

public:
    void setheroname(string hm)
    {
        heroname = hm;
    }
    string getheroname()
    {
        return heroname;
    }
    void setcirc1(int circ1)
    {
        i = circ1;
    }
    void setcirc2(int circ2)
    {
        j = circ2;
    }
    int getcirc1()
    {
        return i;
    }
    int getcirc2()
    {
        return j;
    }
    int getheroHP(void)
    {
        return heroHP;
    }

    hero()
    {
        heroHP = 100;
        heroattack = 10;
    }
};

class enemy {
protected:
    string enemyname;
    int enemyHP;
    int enemyattack;
    int a;
    int b;
    int c;
    int d;

public:
    void setenemyname(string en)
    {
        enemyname = en;
    }
    string getenemyname(void)
    {
        return enemyname;
    }
    void setenemyattack(int ea)
    {
        enemyattack = ea;
    }
    int getenemyattack(void)
    {
        return enemyattack;
    }
    int getenemyHP(void)
    {
        return enemyHP;
    }
    void setEcirc1(int Ecirc1)
    {
        a = Ecirc1;
    }
    void setEcirc2(int Ecirc2)
    {
        b = Ecirc2;
    }
    int getEcirc1()
    {
        return a;
    }
    int getEcirc2()
    {
        return b;
    }
    void setEcirc3(int Ecirc3)
    {
        c = Ecirc3;
    }
    void setEcirc4(int Ecirc4)
    {
        d = Ecirc4;
    }
    int getEcirc3()
    {
        return c;
    }
    int getEcirc4()
    {
        return d;
    }
    virtual void print() = 0;
};

class bottom : public enemy {
public:
    void setbtmhp(int btmhp)
    {
        enemyHP = btmhp;
    }
    void print()
    {
        cout << "I am a bottom, bottom takes - " << getenemyattack() << " from your bottom" << endl;
    }
};
class top : public enemy {
public:
    void settophp(int tophp)
    {
        enemyHP = tophp;
    }
    void print()
    {
        cout << "I am a top, top takes - " << getenemyattack() << " from your head" << endl;
    }
};

int main()
{
    int x = 0, y = -1, ch, gd = DETECT, gm;
    int t = 0, s = -1;
    hero stan;
    bottom btm;
    top tp;
    stan.setheroname("Stan");
    stan.setcirc1(250);
    stan.setcirc2(250);
    int i = stan.getcirc1(), j = stan.getcirc2(); //Giving the position settings of hero circle to var i & j
    btm.setenemyattack(5);
    tp.setenemyattack(5);
    btm.setbtmhp(10);
    tp.settophp(10);
    btm.setEcirc1(350);
    btm.setEcirc2(350);
    tp.setEcirc3(400);
    tp.setEcirc4(400);
    int a = btm.getEcirc1(), b = btm.getEcirc2(); //Giving the position settings of enemy circle to var a b c &d
    int c = tp.getEcirc3(), d = tp.getEcirc4();
    int HP = stan.getheroHP(); //giving the HP settings of hero circle to var HP
    initgraph(&gd, &gm, "c:/turboc3/bgi");
    while (1) //1 represent true in boolean, 0 would have represented false.
    //so while (1) implies inifinity since true goes for everything
    {
        //Circles
        circle(i, j, 5);
        setcolor(LIGHTBLUE);
        circle(a, b, 5);
        setcolor(LIGHTRED);
        circle(c, d, 5);
        setcolor(YELLOW);
        outtextxy(400, 400, "Press Esc to Exit...");
        //Keypad control
        if (kbhit()) {
            ch = getch();
            if (ch == 72) {
                x = 0;
                y = -1;
            }
            if (ch == 75) {
                x = -1;
                y = 0;
            }
            if (ch == 77) {
                x = 1;
                y = 0;
            }
            if (ch == 80) {
                x = 0;
                y = 1;
            }
            if (ch == 27)
                exit(0);
        }
        i = i + x;
        j = j + y;
        a++; // Part I would like to change so that after say every 10seconds, it either goes left or right
        c++; //Part I would like to change so that after say every 10seconds, it either goes left or right

        //Making sure the circles restart when reaches the end of window.
        if (a >= getmaxx())
            a = 0;
        if (c >= getmaxx())
            c = 0;
        if (i <= 0)
            i = getmaxx() - 1;
        if (i >= getmaxx())
            i = 0;
        if (j <= 0)
            j = getmaxy() - 1;
        if (j >= getmaxy())
            j = 0;

        //Circles Overlapping Calculation//
        double T = i - a;
        double S = j - b;
        double D = sqrt(T * T + S * S);
        double sumrad = 2.5 + 2.5;
        double T2 = i - c;
        double T3 = j - d;
        double D2 = sqrt(T2 * T2 + T3 * T3);
        double sumrad2 = 5 + 5;

        //Checking if Circles overlap with previous calculation
        if (D < sumrad) {
            btm.print();
            HP = HP - btm.getenemyattack();
            cout << "Hero Life = " << HP << endl;
        }
        else if (D2 < sumrad2) {
            tp.print();
            HP = HP - tp.getenemyattack();
            cout << "Hero Life = " << HP << endl;
        }
        if (HP <= 0) {
            cout << "END ! " << endl;
            return 0;
        }

        delay(20);
        cleardevice();
    }
}