smiley.cpp

//this is a simple program to draw a simple smiley in a diameter as given by the user

#include<iostream>
#include<math.h>
#include<unistd.h>
#include <sys/ioctl.h>
struct winsize w;
using namespace std;

int main()
{
float j;
int d=1;
ioctl(STDOUT_FILENO, TIOCGWINSZ, &w);
//getting diameter from user and checking whether it is a multiple of 10
while(d%10!=0){
  cout<<"Enter the diameter (multiple of 10)  :  ";
  cin>>d;
//checking whether the terminal of user is big enough to draw the figure
  if(w.ws_col<(d*2))
    {
    cout<<"FIGURE WITH ENTERED DIAMETER CAN'T BE DRAWN IN YOUR TERMINAL\n\a";
    d=1;
    }
  }
//incrementing virtual y co-ordinate
for(float i=0;i<=d;i++)
{
  j=0;
//incrementing virtual x co-ordinate
  while(j<=d)
    {
//checking whether the point can be a part of the circle of given diameter
    if(pow(((d/2)-i),2)+pow(((d/2)-j),2)==(pow(d,2)/4))
    cout<<"*";
//checking for the position of eyes
    else if(i==((d/2)-(d/8)) && (j==((d/2)+(d/4)) || j==((d/2)-(d/4))))
    cout<<"O";
//checking for the position of mouth
    else if(i==((d/2)+(d/6)) && j<((d/2)+(d/4)) && j>=((d/2)-(d/4)))
    cout<<"__";
//leave blank if none of the conditions is true
    else
    cout<<"  ";
    j++;
  }
  cout<<"\n";
}

return 0;
}