0 like 1 dislike
11.6k 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 | 11.6k 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:104.23.190.74
©2016-2025

No related questions found

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