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

0 like 1 dislike
5.3k 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 | 5.3k 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:172.69.7.195
©2016-2024

No related questions found

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