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

0 like 1 dislike
2.5k 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 | 2.5k 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:172.69.7.13
©2016-2024

No related questions found

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