How to draw a horizontal ellipse in C

I would like to know the error in my code. My goal is to draw a horizontal ellipse on the screen.

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

void ellipse(){
     int x,y;
     int center = 30;
     int centery = 30;

     
     for (y=0; y<center; y++) {
         for (x=0; x<center; x++) {
              if((pow((x-center),2.0)/100) + ((pow((y-centery),2.0)/25))< 1)
                  printf("*"); 
              else
                  printf(" "); 
         }
         printf("\n");
     }
}

void main(){
     ellipse();
     return 0;
}
 

But this is all I get in the console :

              ************
           ***************
        ******************
       *******************

but i want this (but horizontal) and without the center :

                    *                        
               *************                  
             *****************                
           *********************              
         *************************            
        ***************************           
       *****************************          
      *******************************         
     *********************************        
     *********************************        
    ***********************************       
    ***********************************       
   *************************************      
   *************************************      
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
 *****************************************    
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
  ***************************************     
   *************************************      
   *************************************      
    ***********************************       
    ***********************************       
     *********************************        
     *********************************        
      *******************************         
       *****************************          
        ***************************           
         *************************            
           *********************              
             *****************                
               *************                  
                     * 

#include <stdio.h>

void ellipse(double a, double b, int centerx, int centery)
{
    double a_sq = a * a;
    double b_sq = b * b;

    for (int y = 0; y <= centery + b; y++)
    {
        for (int x = 0; x <= centerx + a; x++)
        {
            double result = ((x - centerx) * (x - centerx)) / a_sq
                          + ((y - centery) * (y - centery)) / b_sq;
            if (result <= 1.0)
            {
                printf("*");
            }
            else
            {
                printf(" ");
            }
        }
        printf("\n");
    }
}

int main()
{
    ellipse(10.0, 5.0, 10, 10);
}

I changed the following:

• Accepted length of semi-major and semi-minor axis along with center coordinates as function parameters.

• Used type double for calculations.

• Changed the loop conditions - you were using center for for x and y. I changed it so that x goes from 0 to centerx + a and y goes from 0 to centery + b.

• I checked for <= 1.0 instead of < 1 as points on the perimeter of ellipse will have value = 1.

• Removed unnecessary headers.

Seems to work fine here.