10-26 Exercise 3: Find roots of a quadratic equation

Question

Write a program to find roots of a quadratic equation

A quadratic equation is a second order equation having a single variable. Any quadratic equation can be represented as where a, b and c are constants ( a can't be 0) and x is unknown variable. 

寫一個找二次方程的求根程式

For Example

 is a quadratic equation where a, b and c are 2, 5 and 3 respectively.

To calculate the roots of quadratic equation we can use below formula. There are two solutions of a quadratic equation.

使用下列公式:

x = (-b + sqrt(D))/(2*a)
x = (-b - sqrt(D))/(2*a)

where, D = (b*b-4*a*c) is Discriminant (判別式), which differentiate the nature of the roots of quadratic equation.

For the complex result (複數根):

realPart = -b/(2*a);
imaginaryPart =sqrt(-D)/(2*a);

Note: We have used sqrt() function to find square root which is in math.h library.

 

Example input 1:

1 2 1

Example output 1:

Roots of 1.00x^2 + 2.00x + 1.00 = 0 are real and same
x1 = x2 = -1.00

 

Example input 2:

1 -3 2

Example output 2:

Roots of 1.00x^2 + -3.00x + 2.00 = 0 are real and different
x1 = 2.00
x2 = 1.00

 

Example input 3:

1 2 2

Example output 3:

Roots of 1.00x^2 + 2.00x + 2.00 = 0 are complex and different
x1 = -1.00+1.00i
x2 = -1.00-1.00i

Comments

We will continue this question in few days

---

Everything is fixed. Enjoy your time with The Judge :)

---

ANNNNNNNNNNNNNNNNNNNNNNNNNNGRYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY

---

Your code has newline at the end sometime. You learned this lesson many times!

---

After i correct the newline in my code,there is still wrong output.However,I had run the program in Codeblocks.The output is still as well as the result. Seeking for help.

---

your output lack of 1 space at line 8 when print out "Roots of ...". Please be careful with all small details when working with online judge

Answer 1

Hidden content!
#include <stdio.h>
*   **** * * *** **
int main()
{
* **  *  ***** * *  * *  * **    ***** **** ***** **** *     
* ****** * ** ** ** * *  * *    *  * %f ** ** *  *   ** **** ** *   *** 
     * * **** **  *  ****     = (b*b-4*a*c);
 **  *  ** **  ** * ** *** *  = (-b + sqrt(D))/(2*a);
*** ******* ** *  ******  *** = (-b - sqrt(D))/(2*a);
   **  ** * *   *     *  *** *** *** = -b/(2*a);
* * *   ** * ** ** * *   * *      =sqrt(-D)/(2*a);
 * **   **  **      ** *  ***** ** 
  *    ** **   ** ** **** **  
 *** *   *** ** **   **** * ** *  *   *  *  * ** ******* *********  *   * of %.2fx^2 + %.2fx + %.2f = 0 are real and       ***   * 
* ** **   * ***** *   ** * **** *  *     ***   **  * ***  ** ** * * * * = %.2f\nx2 = %.2f",x1,x2);
     **   * *  *    **

***  *   *****  * ****** **  *  if(D==0)
 * *  * * **** * ** * **  
   * *  ***    **  ***  ***** *   ****  ** *** ** * *    ** * **  *  *   of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
 *   *  ****** *   * *   * * ** **  ** ***    * *  *  *   *** ** *** ** * = x2 = %.2f",x1);
**       * * *   ** * ** *******
  ***  * *   *****   **   
  *  **** ***  *** **   ***
  ** *       ** *** * *  *** *  * *  * *  *  * ** *   * ***  *** **  **   of %.2fx^2 + %.2fx + %.2f = 0 are complex and **    *   * * ** * *
**   ***  * **  ****    * *    *  ******  * *** **  ****   ** ***    * *     =   *    *  *    * *    * * 
* ***   **  *    ** *  * ****** ** ***  ***  *   * ****   **       =   *** *  ** *  * ** *  ** 
 ***  ** **** ****   ***** 
*  *   * * ** ** *  * *    ****  0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 2

Hidden content!
#include <stdio.h>
  * ** **  **   **  
int main()
{
**  ** ** *  **  **   **  **   *    **     *   * *        * ** 
*  **  ** *** ** ** ** ** ****  * * *  %f * **    *  ***  **** *  ** *  ******  *
*  ***  * **  * **  * ***       = (b*b-4*a*c);
*  **  ****** * * *  *  * * * = (-b + sqrt(D))/(2*a);
*********  *** ****  * * *  ** * = (-b - sqrt(D))/(2*a);
*     * ***  * *    * **    *****  = -b/(2*a);
 **     *  *  * ** * **   ***   * *   * * =sqrt(-D)/(2*a);
*  * *   *   ** * * ***   *   ***
 *    * ***   ***      * **
  * **** * *** *  * **   *   *****   *  ** * ** *   ** **  ** *  * ** *** of %.2f x^2 + %.2f x + %.2f = 0 are real and * ** ** *  **  ** 
    * *  *  ***  *   * *   **** ****  *       *  *   * * = %.2f\nx2 = %.2f",x1,x2);
** *** *** * * ** * * **** *** 

* ***    **  * **  *  ***     if(D==0)
  **  ** * * ** ** ****    
* *******  *** **** *  *  *******   *** * *    *      * *  * of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
   *** *  ****  ***** **  *****   **   *** **     *   * *** ***** * = x2 = %.2f",x1);
  *** * **  * **  * * 
 *** *******     *     * **
*   * *   ****  **** **** *
****   * **** ***   *  *     * ***** **  ** * * *    *** * ** **    *     of %.2fx^2 + %.2fx + %.2f = 0 are complex and * * **    **   **
***  ***         *** *      * *** **** **  *****      **  *** ** *   =  * ** **** *  * **  ******  * 
  * ***** **** **  *   * * ****   *** ** *  *   * * *** *  * * *  *** * * = ***  * ** *   ***   * *   
  **** **  **   ** ***   *
  ******* **         *  * * ***** 0;
}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output
Case 3: Wrong output

Answer 3

Hidden content!
#include <stdio.h>
#include <stdlib.h>

int main()

{
**  ****    * * **  **     ** a,b,c,x1,x2,D=0;
****   **** ******   ** **
    ******  ****     *    *** *** * ** * %f   *   * * * *    *** * *   *  ** 
   **   * ****** ** * ***
*** * * * * ****   **   **  * **** ***
  ** * *** **    **  ***   + sqrt(D))/(2*a);
  **  * * *** *  ***  *******  - sqrt(D))/(2*a);
* ****   * *   *  *** *  *  
  ***   ***** *  *** ** * *       *  
* *   * ** *     ** *    *** 
   * * * ** *  *      *    ** **** *** ***  ** ***     * *** **   of %.2fx^2+%.2fx+%.2f=0 are complex and * ** * * ** * * **  *  *   *    *
 * * *     *** ***  ********* 
* ******   ** ** *** **  
       ** * ** * * ** * ** *  if(D==0)
 * * **  *    **      ***   * *  
 * *     * *   ***** *     * ***** *   * **  * ** * * * *** of %.2fx^2+%.2fx+%.2f=0 are real and same\nx1=x2=%.2f",a,b,c,x1);
**   *    * *****  *******  
*    ** * **** ** ** ****** ***
  * * **** *     * ***   * 
* **  **** **** **     *  *
  ****   ** *** * ***** *** *  ** ***** *   *  ***   ****  *  * of %.2fx^2+%.2fx+%.2f=0 are real and  *  ** *     ** * ********  ****  
   *    * **** ** **  ***  * 
*    * **  *  *   *   ** * *  
**   *   *   * * ****   * *
  *  *    *** **** *  **   0;
}

Comments

prog.c: In function 'main':
prog.c:12:14: warning: implicit declaration of function 'sqrt' [-Wimplicit-function-declaration]
     x1=(-b + sqrt(D))/(2*a);
              ^~~~
prog.c:12:14: warning: incompatible implicit declaration of built-in function 'sqrt'
prog.c:12:14: note: include '<math.h>' or provide a declaration of 'sqrt'

Answer 4

Hidden content!
  **    ****  **    * 
int main()
{
  *   * ** *** *****    * **  ** a,b,c,D;
  ** *** *  **   ** * * **  **  x1,x2,r,i;
**   *     * *   *   **   * * *   *  *  * *****   ** **   *  *   **
 *  * ****  *   * *** *  **** ***** 
 *   *  ****  * **** **  ****** *  *  
      ** *  *   ** * *  *** ***    ****  **** * *
   * * *      *** ** *
***  * ** *****      ** ****
 *  ***  *  * ** **    *      * * *  ***  * **  **   ** *  *    **  **** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
*** *  ***   * ***  **  * * * *   * * *     * *  *  * *  *  *** *** = x2 = %.2f",x1);
*  *   ***  * *** **  * 
      *   * *   * **  *  *   * if(D>0)
*** ** * * **** *  * ** * * * *
*   **     * * ***    * ***  * ***    *    *   * ***     of %.2fx^2 + %.2fx + %.2f = 0 are complex and ** * *    * * *** *  *
* **   *  ** ***     * * *      **  *  * * ** *  *    ******* * ** * *  = %.2f\n",x1);
*** *      *   * *  *** *     * ** ** * ***   * * *  *  ** ** * *** * = %.2f",x2);
** **  * *** ** ** * **  *
*   **      ** *    *    if(D<0)
* *     * **   *    * * 
* *********   *****   *** **  *    ** ** ***** ** * * ** * ****     of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
***  * *     *   * * *   *  * *** *    *******  *  ** -b/(2*a);
 * *  *    *** * ** ** ** *      ***  **** * * ** ** **** *****   
  **  **  * *      *    *  ** **   ***  *     * **   *  ****   *   = %.2f+%.2fi\n",r,i);
* * * *  **  ** * **     ** ** * **  *  * * *  ****   *****  ** *** *      = %.2f-%.2fi",r,i);
* **   * *    **   *  *  *
}

Comments

prog.c: In function 'main':
prog.c:6:5: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
     scanf("%f%f%f",&a,&b,&c);
     ^~~~~
prog.c:6:5: warning: incompatible implicit declaration of built-in function 'scanf'
prog.c:6:5: note: include '<stdio.h>' or provide a declaration of 'scanf'
prog.c:12:9: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
         printf("Roots of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
         ^~~~~~
prog.c:12:9: warning: incompatible implicit declaration of built-in function 'printf'
prog.c:12:9: note: include '<stdio.h>' or provide a declaration of 'printf'
prog.c:17:9: warning: incompatible implicit declaration of built-in function 'printf'
         printf("Roots of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
         ^~~~~~
prog.c:17:9: note: include '<stdio.h>' or provide a declaration of 'printf'
prog.c:23:9: warning: incompatible implicit declaration of built-in function 'printf'
         printf("Roots of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
         ^~~~~~
prog.c:23:9: note: include '<stdio.h>' or provide a declaration of 'printf'

Answer 5

Hidden content!
 *  * *** *   * * * * 
int main()
{
**** * * * ** * *   **  *  *    a,b,c,D;
 ** **  ** *  *  * *** * ***  *  x1,x2,r,i;
***  ** ** *****  *****     * **     * ***    ***  *  **  * ** * *  *****
** ** ** *  *   **  ** *   *   **
** *** *** ** * * * ****   **   *  * ** 
     **   **   *   * ***     *** **    *  
** * * * * **   * **   ** **
   * *   **   ***  * * *****    
* * *  *  *   *** * ** * * * ***  *  * ***** ** * ** *      * ****** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
 *   **** * * ****** **    * ***** * ***   **  *   ** *  *** *  = x2 = %.2f",x1);
  *  * * *  *  *   * **** 
*    *   *    *   * ***** **    ** if(D>0)
** ** * *  *   ** *     * 
*  **** * * *  **** ** *   *** *  **  ***** * * *   * *** *  **   ** of %.2fx^2 + %.2fx + %.2f = 0 are complex and      * ***   * ***  **
 *   * *   ** *     ** ***  * **  * * * ****   *     * **  ** *   ** = %.2f\n",x1);
   *** * *** **    * ******* *    **** * * * *   *  **  * ** ** ***   = %.2f",x2);
  ** *    *** * *******  * ** 
 ** * **** *  **   * * * *** * if(D<0)
*   **  * ** ***** *  **    *
*** **   * *   * *  * ** * ****** * * ** *      *  ** * **** * *    of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
*  * **   ** **** ***    *  * ** ** *   ** *  **  -b/(2*a);
***      *    ***  * *  * ** * **   **** * ** * ** **  ***** **  **
**** *      ** *      ***  * ***   *   **** ******** **   *  *  * * = %.2f+%.2fi\n",r,i);
****     **** *** ***  **  *     *  * * * ********* ** * *  *  *  * = %.2f-%.2fi",r,i);
    *****  * ** * ** ****
}

Comments

prog.c: In function 'main':
prog.c:8:12: warning: implicit declaration of function 'sqrt' [-Wimplicit-function-declaration]
     x1=(-b+sqrt(D))/(2*a);
            ^~~~
prog.c:8:12: warning: incompatible implicit declaration of built-in function 'sqrt'
prog.c:8:12: note: include '<math.h>' or provide a declaration of 'sqrt'

Answer 6

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int main()
{
*** **  * * **  ** * *    * a,b,c,d,x1,x2;
**  **  *     *** *******  *     * ****   **  *  *** *   * ***  **   
 *****   *   * *  *  * * * **  * * 
**** *****  *  *** * *   ** * ***  ********
*  ***  * ** ****  *   * ** *  **   *   *   
**** *     ** **  ****** *** *   *  ****
 *   *  ********   *  *    ****
** *   * *       ***** ** * ***  ****  ** * **   * *** *** of %.2fx^2 + %.2fx + %.2f = 0 are real and *** *  * ** *  ** **
*** **  *  *  **  *** * * ***   * *  * ***  ** ***  *  * *    **  * = %.2f\n",x1);
*  ** * **   *    ***  * ***      * * * * * *  ** *  * * *  ** * *** *   = %.2f",x2);
 ** * ** ** ** * **   * *
 * *  *** ****  * * *** ****      if(d==0)
*  ****  *    ** * **** *** 
  ** ****   **  *  ** *** **    ***** ****  **  **      * **** *  of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
  * * *       * *      ***  **   ******* *  ***  *** ** **** *  ** * * = x2 = %.2f",x1);
  * * *  ***        * ** **** 
  * ***     * * **  *  ** 
    **  *     *   * * **  
*****   *    * *** * *  * ** ***     * ** * * *  ***   ** **    of %.2fx^2 + %.2fx + %.2f = 0 are complex and ** * *    **   ** * 
 *****  *****  **   ** ****  *  *** * ** *   * ***** *  *** * * **   **  =  *** **   **    **** **  **  *   
* ******* * ***** * ***   * **  ********  **** *    **  **  *** *  ** * = * ***** * * * * ****** * *   ***    *
      *****          *** *** 
 * **** *  ** * *****  * *   0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 7

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main()
{
  ** *    *  * ****    **  * *** ** a,b,c,d,x1,x2;
 * * ** *** ** *  ***    ****  *   * ***   ** ***  **  ** **  ***   
 *** *** *** *****  ** *  *  **** * ** *
* ***     *******  * ***   **  = (-b + sqrt(d))/(2*a);
   ***  ***** * * *  ***  **** = (-b - sqrt(d))/(2*a);
*  *  ****** **  *  * **    *  * *   
 **  *   *****  ***    ** ** ****  ***    *****   **  ************  of %.2fx^2 + %.2fx + %.2f = 0 are real and different\n",a,b,c);
* *   *      *** *    *   * ** * *   ** *  ******    *     ** *****  *   ** *     * ** * *      ** ***  *   ****    * *    * ** * ****  * ***   **** *** **   * *** **   ** ** ***  **    **        ***     *** *    * *****   * = %.2f\n",x1);
 ****    * **** ** ** *  *** *  ** *   **       **  * ********   * **  ***    * * *     *  ******       *  ***  *** * **** ****** **    ** * **  *  * *   **** * * * ***  ****     * **     *  **  *   ***  *** * **** *** * * ** *   * * = %.2f",x2);}
  ****** ***  * **** ***** * *** if(d==0)
 * **   * **   *     * * * *    * ** ***    **  
* *     * *   * * *    *****  ***  **    ***      * *  **** **** *  * * *   * ****   * *  *  of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
**    * * ***  *  *     *****            * **   ******   **    *    ***  *     * * ** **** ***  * **  ** ****   **** * ** **  **  ** * * **  *  * *    = x2 = %.2f",x1);}
* *  *  *       *  * * *  *** 
*     *  * **    *  * *    *  *****  *     *     *  * *   ***   * *** * of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
***   * *  *   ***  *   *****   * * ** * *   * **   ***  *     ** ** **  = *  *    *    ******   * * *** 
**   ******   * ******   ** *** *  *** * *  * **    *  * * * =   ***  ***  **** *    **
 *  *  ** * *  *   ***   **  ** 0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 8

Hidden content!
#include  ****   ** *** **
#include ****   *  ***

int main()

{
  ***  ******  *    * *  **   ***       ** **  **  * * *
 * * ** *  **** *  *   ** * ** *  ***  * %f  *  ** ***** *** **  * *   * ****

  *  ** * *  * ***** ** **    
*   *   * *  *** * ** *****  + sqrt(D))/(2*a);
     **   * **** *  **   **    -   * ** 
 **  * ****   * * * * **** *** *** *
   ***   **    * * *** *      **  *  *  ** 

**  *** * * ****  ** *    **** (D==0)
*  *  **  *   *** ** ** * *
**  ***** *  *   * **   **  **   ***********  *** *  *   ***  ***  *  of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 =  ** ***** *  * * *
*    ** **    *  ***   **  
 *  *  **  *   ** * **** *   if (D>0)
    *  *  **   **  ** * ****** 
 **** **  ****    * * ******  * *** **   *   **     * * ***** of %.2fx^2 + %.2fx + %.2f = 0 are real and different\nx1 = %.2f\nx2 =  *  *   ** *   ***  **
  ***  ***** * **   ** ** *  
 **   * **  ** *  *   * * *****
* * *  * **   ****     **   **   *
      * *  * * *   * ***  *   *** **** *  ****   ***  ***** *********** **  of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\nx1 = %.2f+%.2fi\nx2 = ** * * *  * * *    *   *  * 
 *  *    ****  *******  * 

**** *****   *    * *  *** * **       0;

}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 9

Hidden content!
#include **  **   *  *** *
#include * **   *  **** *
int main(void)
{
float a,b,c, D, x1, x2,i;
   *  *      **   *  * **  *    ***   *** %f    *     &a, &b, &c);
  * *  * * ******  * * **   *   ** *  ** 
** **   **    **** **** *** *     (D>0)
 ** * *     ***   **     **   
** * ** *** ** * *  *  ** *             **  *    * *    **** 
*** ** ***  *** * * ** ***  **   * **    * ** *  **   *  ***  ******* ** 

   ***** ****** **  * ******** ****   * **  **  * ***  * *  * **  **  ***  **   ** *    of %.2fx^2 + %.2fx + %.2f = 0 are real and **    * * = %.2f\nx2 = ***  ** *   **  
  ****   *  ** ***   **  ** 
    * **    **** ***** * **  ** if (D==0)
  **    *   ** ** **  *
   ****  * * * **   *      * * **   *    * ***   * *   **** ** * **  
** * * ******* ** **  *   ** ** * *     *** *        *   ****  of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = *    * **  * 
* ** ** ****  * **  * ** * 
 **  *   *  ********  *  ******  
*** *** ******    * *  ** * *
* * ***     *  **  ***  *   *       x1=x2 = -b/(2*a);
*****    *     **     **  ***  ***  **** **   *  *   *  
 *  * *     **      *   *   ** *  *  **** * *      ** * *   **  of %.2fx^2 + %.2fx + %.2f = 0 are complex and **   ****  = *   * ** * * = *** *  *    ******  x2,i);
*** *  *    *  ***** 



* **  ***    * *  * *  *     0;
}

Comments

prog.c: In function 'main':
prog.c:10:16: warning: implicit declaration of function 'sqrt' [-Wimplicit-function-declaration]
         x1=(-b+sqrt(D))/(2*a);
                ^~~~
prog.c:10:16: warning: incompatible implicit declaration of built-in function 'sqrt'
prog.c:10:16: note: include '<math.h>' or provide a declaration of 'sqrt'

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output

---

prog.c: In function 'main':
prog.c:21:5: error: expected ';' before '{' token
     {
     ^

---

Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output

Answer 10

Hidden content!
#include **   *   ** *   
#include   ** * ***  * **

int main()
{
 *      ***   **  **  ** *   * * * a, b, c,   ****  x1,x2, realPart, *  ****      


*   ******* * * **    *  * ****  %lf *  ** * ***    &b, &c);


** *  *      * ****   *  ***   *** ** = b*b-4*a*c;

*  *  **  *   *  * ******* condition for real and different roots


  **** *** **********   * *** ** * for real and equal roots
* *** **  * * **   *  ** **  **   (determinant == 0)
   * * ** * * *   ** ***** * 
* * **  * *    **  **      **** *** **** **     **   ** = x2 = -b/(2*a);
  **** *    **     ***  *  * **** ** **  *         * *  * *   ** *    ** of %.2fx^2 + %.2fx + %.2f = 0 are real and *  ***   * a,b,c);
 **  * ** **  *    **    * * **  ***  ** *** * *****  **  * **  *  **  = x2 = ** ***   * *** x1);
 * ** *      *  ******* 

  *   ***  *** * *****   **  **** *     ***  if (determinant > 0)
** *  * ** **   * ****         *
* ***  *     * * **    **** sqrt() function returns square root
 *** *** * * *  * *   * * ** * **  * *****    *  * *** =   *** ***    ** *  *
 ***  *  *     ******* * *** * ********  * *** =  * *   **   *   *  *

* *  **    *  * * * **  **   **    *** ** * * *   *****    ** **  * *** of %.2fx^2 + %.2fx + %.2f = 0 are real and *    * * *   *  ***
**  ***  **   **  ** ** ** * * ****  *   *      * ****** * ** =     *****   x1);
*  ** *** *  ****** *    *****  *  *** * * * *** *  ** *** *    *** ** =  **  ** * x2);
   *   ** *** *      **     ** if roots are not real
**   * *  *** * * * *     **   ***
*  *   ** * ***  * *  ****   **
      **    **     *    **  ** **      **   * ** **** **  = -b/(2*a);
  ****  * *    *******  * * ** * * * ** **  * *  * *  *** **   = ** *** * **  **  * 
 **  ** *   ** *   **  **** **** ******  * **  *  * * **   ***   *** ** of %.2fx^2 + %.2fx + %.2f = 0 are complex and * *  *** *     a,b,c);
  *  *  *** * **    * ***  ****  * ** *** * * * ****** * *      * =  * * ** * * * *  realPart, ** **** ** ***
  ** *  **   ** * ** ***** ** **  * * *   ***  *  * *  *** * * *  * **  = ***  *     *  realPart,  * ******
  ** ** **   *******     **

  *** ***** *  *  ****  **  * 0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output