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

0 like 1 dislike
2.4k 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 | 2.4k 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:172.69.58.212
©2016-2024

No related questions found

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