0 like 1 dislike
9.2k views

Write a program to find roots of a quadratic equation

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 | 9.2k views
0 0
We will continue this question in few days
0 0
Everything is fixed. Enjoy your time with The Judge :)
0 0
ANNNNNNNNNNNNNNNNNNNNNNNNNNGRYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
0 0
Your code has newline at the end sometime. You learned this lesson many times!
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.
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

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
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
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
0 0
-----------Re-judge-----------
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
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
Welcome to Peer-Interaction Programming Learning System (PIPLS) LTLab, National DongHwa University
English 中文 Tiếng Việt
IP:172.70.100.122
©2016-2025

No related questions found

12,783 questions
183,442 answers
172,219 comments
4,824 users