#include <curses.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>

#define MAX_BLOCKS  3000
#define MAX_ITERS   1000
#define ROW_LENGTH   100
#define U_SECONDS  50000

int main(void)
{
    int x = 0, y = 0;
    bool stars[MAX_BLOCKS];

    initscr();
    cbreak();
    noecho();
    clear();

    // Draw the initial field of dots.
    for (int i = 0; i < MAX_BLOCKS; i++)
    {
        stars[i] = false;
        mvaddch(y, x, '.');

        if (++x == ROW_LENGTH)
        {
            x = 0;
            y++;
        }
    }

    refresh();

    // Randomly flip blocks between dot and star.
    for (int i = 0; i < MAX_ITERS; i++)
    {
        int n = rand()%MAX_BLOCKS;
        stars[n] = !stars[n];

        y = n/ROW_LENGTH;
        x = n%ROW_LENGTH;

        mvaddch(y, x, stars[n] ? '*' : '.');
        refresh();

        usleep(U_SECONDS);
    }

    mvaddstr(MAX_BLOCKS/ROW_LENGTH + 1, 0, "Press any key to quit");

    refresh();
    getch();
    endwin();

    exit(0);
}