Write a C program to design flying characters Screen Saver

Below is the source code of the C program to design flying characters Screen Saver which is successfully compiled and run on the windows system.The Output of the program is shown below.

SOURCE : :

#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
 
/*will return character based on passed number*/
char getCHAR(int n)
{
    char ok[]="~!@#$%^&*:;'",{}|<>=";
    return ok[n];
}
 
/*function to identify that any key hit by the keyboard*/
int kbhit(void)
{
  struct termios oldt, newt;
  int ch;
  int oldf;
  
  tcgetattr(STDIN_FILENO, &oldt);
  newt = oldt;
  newt.c_lflag &= ~(ICANON | ECHO);
  tcsetattr(STDIN_FILENO, TCSANOW, &newt);
  oldf = fcntl(STDIN_FILENO, F_GETFL, 0);
  fcntl(STDIN_FILENO, F_SETFL, oldf | O_NONBLOCK);
  
  ch = getchar();
  
  tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
  fcntl(STDIN_FILENO, F_SETFL, oldf);
  
  if(ch != EOF)
  {
    ungetc(ch, stdin);
    return 1;
  }
  
  return 0;
}
  
/*move cursor on specified position on screen*/
void gotoxy(int x,int y)
{
printf("%c[%d;%df",0x1B,y,x);
}
 
int main(void) {
    int x,y;
    long int i,j;
    i=j=0;
 
    x=1; y=20;
    system("clear");
 
    /*program will run until any key hit*/
    while(!kbhit())
    {
        x=rand()%((150-1+1)+1);
        y=rand()%((50-1+1)+1);
        gotoxy(x,y);
        printf("%c", getCHAR(rand()%((20-1+1)+1))); fflush(stdout);
        ++i;
        if(i==10000) {++j; i=0;}
        if(j==100000){ i=0;}
        if(j<=100)
            usleep(30000);
        if(j<=1000)
            usleep(3000);
        if(j<=10000)
            usleep(300);
    }
    return 0;
}