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

0 like 1 dislike
5.2k views

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
[Exercise] Coding (C) - asked in Chapter 5: Selection Statements by (5.2k points)
ID: 28934 - Available when: 2017-10-26 18:00 - Due to: Unlimited
reopened by | 5.2k views
0 0
We will continue this question in few days
commented by (12.1k points)
0 0
Everything is fixed. Enjoy your time with The Judge :)
commented by (12.1k points)
0 0
ANNNNNNNNNNNNNNNNNNNNNNNNNNGRYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
commented by (-249 points)
0 0
Your code has newline at the end sometime. You learned this lesson many times!
commented by (12.1k points)
0 0
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.
commented by (-214 points)
0 0
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
commented by (9.9k points)

56 Answers

0 like 0 dislike 
Hidden content!
  * ******   * * *     **
# *****   **    *  ***  
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 complex and   ** **    ** ****  * 
 ***     * ***    * * * **   *   * * *     *  * **** **       = -%.2f+%.2fi\n", realPart,imaginaryPart);
 **  ***   * *** *  *  *  **** * * ******  *   * * *   **   ***** *** = -%.2f+%.2fi", **** *   ******
******   * **     *  *   * * 
  ** *  *****  ** *** *** **  if(D == 0)
*  *  **   **  **  *     ***

**** *        * *   ** *****    ***   * *  *    ********   *    *     of %.2fx^2 + %.2fx + %.2f = 0 are real and ** ***  **  *   
  *  * **   *** ** * ****  **** **  ** * *   ******  *    * * *  = x2 = %.2f", x1);
****  * **      ** * *** ***   
 *  * *****   * ***   *  
*    ** *********  *** ** *    * 
  * **   * **   * ***  *     *     * * *  * **   ** **    *  * *   of %.2fx^2 + %.2fx + %.2f = 0 are real and ******   * *   ** ** 
******* * ** *  **  * ** **     * * ***    **   *  ******* ** = %.2f\n", x1);
* **    *   **   *  *** *** ** * *  ** *    *** *****   ***  * ***  ** ** = %.2f", x2);
* *** * *** ** **  **       **  **
* *  *   **  * *  *   ** *  0;

}
answered by (-281 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
/tmp/ccgUqSsU.o: In function `main':
prog.c:(.text+0x87): undefined reference to `sqrt'
prog.c:(.text+0xd5): undefined reference to `sqrt'
prog.c:(.text+0x14c): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output
commented by (4.3k points)
0 like 0 dislike 
Hidden content!
#include  *** **   ** * ***
#include <math.h>
int main()
{
 * *   **** **  * ***** **  *   a,b,c,x,y,d;
*  ** **    *   ** ** *   *  ** * %f * ******** ** * ****    * **
 *   **  *   ** *  *  *  *   * ** * * **
** *** * *   *   *    **** ** *   *****    *
  ***   *    *** * ** *****   *   * * 
*    * * *******    ** *  ** (d>0){
* ***  ** **** **  * *    * * *  * **  **  of %.2fx^2 + %.2fx + %.2f = 0 are real and * ***     **    *
 ** *           * *** **  *  *  **** **  *     = %.2f\nx2 = %.2f",x,y);
 * **   * *****  *  * **   ** 
   **   * *  * **   **  *  *  *    if (d==0){
  ***    ** *  *** * * **  *   *   * *  *     * of %.2fx^2 + %.2fx + %.2f = 0 are real and *** **  *  * 
 * **      *   ** * ***    * *  ******          = x2 = %.2f",x);
*** *   *    *  *  ** *   *
  * * * *  *** ** *    *       
  ***  * *  *  **  * *****    ***    
*   ***     *  **      * * *** ***   *    of %.2fx^2 + %.2fx + %.2f = 0 are complex and   ** * *   * ***  ** 
 ** *    **  **  **  *** * **  ** *   **
* ** *   *  ***      * ****   *** **** ***  = * ***  *   * ** ***   **
 **** * * ****  **  * *   *  ****  * =    *     ** ***   
  **   ***  **     * *   *

* *   ** **  * *    ****  **  0;
}
answered by (54 points)
0 0
/tmp/cc8k7Xv8.o: In function `main':
prog.c:(.text+0x87): undefined reference to `sqrt'
prog.c:(.text+0xd5): undefined reference to `sqrt'
prog.c:(.text+0x21f): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 like 0 dislike 
Hidden content!
#include *    **  *   * *  * 
**    * * ** ** **** *

int main()
{
***  ** **** *     ****   ***  a, b, c, D, *** **    realPart,  * * ***

 *  **   *   * ** ** *    *  **    * ** * %lf   ** *  *  *   *  **   *  ** ****

** ** * *** * * **  **  * = *  * *

   *  **  *       *    * ** *  (D > 0)
** * ******* * * * ** * ***     
* ******     * ****      ***  **  **     ***  *** ** = ***    *  ***
 *   *** * ****    *   *********  *     * ** *   *** =  *    *    *  

  * * *** ** *  * * * *        **  ** **  *  * * *  *  ** *******   * of %.2lfx^2 + %.2lfx + %.2lf = 0 are real and  * ** * = %.2lf\nx2 = * * **** * * **  **  b, c, root1, root2);

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

 ** ***** *  * * *  ** ***   *** if (D == 0)
  **  *  **    ** *    **   **
    ****     **    *** *** * ** **** * *** ****** * **      = root2 = -b/(2*a);

** **  *  ** * * * ** * ******* ****  ***  ***** *   *   *  *   of %.2lfx^2 + %.2lfx + %.2lf = 0 are real and same\nx1 = x2 = *       ** a, b, c, root1);
 ***  * *      *    * *   

***   *** *    *  **   *   **** ** 
***     *   **  *  *** 
 *     ***** * **     ***  *** ***  *   *      ***** *   = -b/(2*a);
*  ********** *** *  *  *      *** *  **** *    *      ****  **** **  =  *     *    

  *  * * ***** *  * **     ** *  *  *** * * *  *  *       * *  ***   * ** ***** * * of %.2lfx^2 + %.2lfx + %.2lf = 0 are complex and  * *  * =   **  ***** = *    **  * *** a, b, c, realPart,  * ** * * realPart,    **      
  *    * *** **   ****      *  

  * ** *     ** **  ******  ** **  * * **  *** * 
*  *    *** *  * ** *   ** *   0;
}
answered by (5.2k points)
0 0
/tmp/ccibyL4w.o: In function `main':
prog.c:(.text+0x89): undefined reference to `sqrt'
prog.c:(.text+0xd4): undefined reference to `sqrt'
prog.c:(.text+0x1fc): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
/tmp/ccfjcMIR.o: In function `main':
prog.c:(.text+0x89): undefined reference to `sqrt'
prog.c:(.text+0xd4): undefined reference to `sqrt'
prog.c:(.text+0x1fc): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
commented by (4.3k points)
1 like 0 dislike 
Hidden content!
#include <stdio.h>
#include <math.h>

int main()

{
   *** *  *   **** *****  **     * * * ** ** *  ** *   ******* *

  * *  ** *** *  ***   **   * ** * * *     *  %2f * * *    ***** * * ** **   *** 
 **  **  *  * ** ** * = (b*b-4*a*c);
 *   *** * **** ** *****  *   = (-b + sqrt(D))/(2*a);
 ***    * * *     **    *** = (-b - sqrt(D))/(2*a);
***  *  * * * *        *  * **   * = -b/(2*a);
 ** * *    **** ** * * *** **   *  **  =sqrt(-D)/(2*a);

           *  * * *  **** (D==0)
  *******     **       *     
   ****   * * *    *  * * * **  ****     **  *   ** *    ***   of %.2fx^2 + %.2fx + %.2f = 0 are real and ** *** **  ***
*****  *  * *  *  *  *    **** *  *  * *  * ** *  **  ** * * *  ** ** = x2 = %.2f",x);
** *   *   *  * ***   ***        *
   *   * ** * ***** * ****      * ** if (D>0)
 *    * **        * * ***  *    *
 * ***  ***** * ***   ****** * *   *  * ** **** *  *  *   of %.2fx^2 + %.2fx + %.2f = 0 are real and * ***   ********  
*** *  *   * * ** * ***     *  *   ** *  * * ***        *  ******** **  = %.2f\n",x);
 * ** * *** *  ***  ***** * *  *** *  **** * ** ** ** **   ** ** *   = %.2f",xx);
*      * ** **  * *  **  *   *
** *  **   *** ** ** ***** ****
   * * **    *   *  *  ***  
  **** *******  *    **    * ***** *  **   *  ** *  **   *  *** *** * of %.2fx^2 + %.2fx + %.2f = 0 are complex and   **  *  *  * 
 *** **  * * ** *  *   *   ** **  * * * ** * **           ******   =  ** *  ** ***      *** *** ********   
*  * *  * *** * ***** ***  * ****  **   **** ** * ** *  *  * ***   ** = *** ** *   ** * **    *  *****   *****
** * *****    *   * **  ****  * 

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

}
answered by (-249 points)
0 0
/tmp/ccwpNp77.o: In function `main':
prog.c:(.text+0x87): undefined reference to `sqrt'
prog.c:(.text+0xd5): undefined reference to `sqrt'
prog.c:(.text+0x13e): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
/tmp/ccWys99e.o: In function `main':
prog.c:(.text+0x87): undefined reference to `sqrt'
prog.c:(.text+0xd5): undefined reference to `sqrt'
prog.c:(.text+0x13e): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
commented by (4.3k points)
1 like 0 dislike 
Hidden content!
   *** *******     * **
     *   ***    ** *
int main(){
*  **** **   *  ** * ******* * a,b,c;
 ** *** *  *  ****** ***** *   D;
 ** **    **     ** ** *    * * * ** *****    %lf  ** **  ** *   *   * * *   ***    
**    *    ** ** *  ** *  * * ***   - 4*a*c ;

**      * * ****         **    * **   of %.2fx^2 + %.2fx + %.2f = 0 * **  *  ****

*   ****** *****  * **  **    * **  * **
 ** *  **  **     *****    ******   * *          * * *** ** ** ** * *  complex and  **  *  ******* **
*****    *  ** **   ****  **  *     *** ** *******           *******   *  =    *   *** *  * (-b) / (2*a) ), sqrt(-D) / (2*a) );
**** * * *   **  ** ******* ** **             *** * * ****  * *    =  * * ***       (-b) / (2*a) ), sqrt(-D) / (2*a) );
** ** *    * * ****    *  ** 
 ***   ****     ****** ***   * ** if(D==0){
 ***   * ****    * **  ***       **  * ********  * ***  * ****   ** *  ** real and same\n");
  *  *      **  * * *  * ** *    * **    *  **  *    **   *  = x2 = %.2f",( (-b) / (2*a) ) );
 *** ***** **  **** *  *  *  
*   *  **   * * **     ***       **
 **    * *     ** **   * ** *  ** ** * *   **** *      **** ***** *    real and *   **** *****
 **  *  * *   * * * * **  * ** *****  *           *** **   **  = %.2f\n",( ((-b) + sqrt(D)) / (2*a) ) );
  ****  *** ****** ** ***  **** ***    ** ** ***  *   **    * * *     = %.2f", ( ((-b) - sqrt(D)) / (2*a) ) );
   *     *  ** **  *  * * 

*  *** * ** * * ***  ***      *  *  * 0;
}
answered by (-116 points)
0 0
/tmp/ccpv8G38.o: In function `main':
prog.c:(.text+0x51): undefined reference to `pow'
prog.c:(.text+0xdd): undefined reference to `sqrt'
prog.c:(.text+0x13f): undefined reference to `sqrt'
prog.c:(.text+0x213): undefined reference to `sqrt'
prog.c:(.text+0x26a): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
commented by (4.3k points)
0 like 0 dislike 
Hidden content!
#include <stdio.h>
#include <math.h>

int main()

{
**   *    ** * * * **  * **  *** * *  ** * ** *  

* *   *  *  *    ** * * * ******** ** * %2f * ** *** * *   ***  * * **  *
**   * *   * ********** *  ***** * = (b*b-4*a*c);
* *   ***      *  * *  * = (-b + sqrt(D))/(2*a);
  *** ***  ***** *** *   ** = (-b - sqrt(D))/(2*a);
   **  * *  ****  **  **         ** = -b/(2*a);
*     *   **** * * * *** ** * *  *  =sqrt(-D)/(2*a);

* ** ** ***  **   *   **  (D==0)
*    ****    * *   **  *  ****** 
*  **  **   *  * ** **    ***    *  * **     *      **** *    ** *** of %.2fx^2 + %.2fx + %.2f = 0 are real and   *** *  * *  
 * * * *  *** * **  **   *  *   **  **  ****  **  ** ** * ** ** *  * = x2 = %.2f",x);
  **   **     ** ******* **   **
  **     ** ***** *** * **  **  if (D>0)
* *** * * ****  * **    *
 **  * **** ***   ***   * ***    **    ********  * *****  * *** * **  * of %.2fx^2 + %.2fx + %.2f = 0 are real and *   *    *   ***
* *****     *   * *  *** ***  *  ** * * * *     ** * *   *** *     = %.2f\n",x);
* * ***  * * **   ***** * *** ***** * * *** * ** **   ** *  * **  = %.2f",xx);
** *  *    *  * * *  *   * *
****   * *** ***    * * ** 
 ******* * *** *  * *   * **
* *** **   *******    *  ** * * ** *  ***    * * * *     ** *** *      of %.2fx^2 + %.2fx + %.2f = 0 are complex and * ********** ****  *  *
* **  * *    ****   **      **   *     ****   **** ** ***  *** = ****** *  *** * **  *      * ** **   
*   *  ** ****      **  **   **** * * *  ***   *   *  *  *  **  **  * = ***  *  ***  * *** * ** *** 
 *   * *     ***     ****

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

}
answered by (-249 points)
0 0
/tmp/cckgLAYq.o: In function `main':
prog.c:(.text+0x87): undefined reference to `sqrt'
prog.c:(.text+0xd5): undefined reference to `sqrt'
prog.c:(.text+0x13e): undefined reference to `sqrt'
collect2: error: ld returned 1 exit status
commented by (4.3k points)
Page:
Welcome to Peer-Interaction Programming Learning System (PIPLS) LTLab, National DongHwa University
English 中文 Tiếng Việt
IP:108.162.216.36
©2016-2024

No related questions found

12,783 questions
183,443 answers
172,219 comments
4,824 users