0 like 1 dislike
11.9k 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 | 11.9k 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 ***** &a, &b, **
* *** * * * * * *** * *
* *** * * ** * * ** ** *** * ** *** {
***** **** * * * ** * * ** ** ** * ** * ** of %.2fx^2 + %.2fx + %.2f = 0 are complex and * * * * * = * * * ** = * *** ** * a, b, c, (-b)/(2*a), *** *** (-b)/(2*a), * **** *
***** * * * ** * *** **
* ** ** **** ** **** if(d==0) {
***** *** ***** * ***** * ** *** ***** **** ** * ****
* * * ** * * * ** *** * *** * * * * ***** * * * of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = * * ** * * * a, b, c, x1);
* *** ** * *****
*** * *** * ** * * ** {
** *** ** * * ** *** * *** ***** * * ** * * * *** **
** ** * * **** ** ***** ** ** * * ** *** * *** **** * **
**** * * ** * ** * * * *** ** * ** ** * *** *** * * of %.2fx^2 + %.2fx + %.2f = 0 are real and ** ** ** * = %.2f\nx2 = * *** ***** a, b, c, x1, x2);
* * * ** * * * * ** **
}
answered
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
0 like 0 dislike
Hidden content!
#include ****** * * **
**** * * * ******
#include * *** *

int main()
{
* * * ** * * * * ** ** ** ***** **
* ** * ****** *** *** * * ** %f * * **** *** *** * * **
* * * ** * ** ** ** * ** *
* * * ***** *** * * ** ** *
**** * * ** *** * * * * * * *
* ** ******* ***** * * **
* * ** ** ** ** *** * ** *** of %.2fx^2 + %.2fx + %.2f = 0 are real and ** * * = %.2f\nx2 = **** * * * * ***
** * ** * ** * * * if(D==0)
*** **** * ** * **** ** * ** ***** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = **** *** * ** * *
** * *** *** * * *** ** **
*** * * ** * * * ** ***** of %.2fx^2 + %.2fx + %.2f = 0 are complex and *** * * = ** * ** = * * *** * * * * *** ** * *** *
**** * ** **** * **** ** * 0;
}
answered by (-498 points)
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
0 like 0 dislike
Hidden content!
#include * * **** * *****
*** * ** * ** ** *
* * * * * * **

int main()
{
** * * *** ** ** * * **** **
**** ***** * ** ** * * * * %f * * * **** *** **** * **** *
** * * * * *** * ** *** *** * **
* ** * * *** ** * **** ******* * *****
*** * * ** **** ** ** **** * **
** * ***** * * ** ** * *
** * * ** * ** * *** * of %.2fx^2 + %.2fx + %.2f = 0 are real and * * ** * = %.2f\nx2 = * ******* * * * *
*** * * * ** ** * * * **
****** ** * * ** * * ***** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = * * ** * * * *
* * *** ** **** * ***** * *
* * * * *** * *** ******** of %.2fx^2 + %.2fx + %.2f = 0 are complex and ** * = %.2f + * *** = %.2f - ** * * ** *** * **** * **** * * *
* * ** ** * * ** * * * *** * 0;
}
answered by (-498 points)
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Wrong output
Case 3: Correct output
0 like 0 dislike
Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include<math.h>
int main()
{
* *** * ** ** * * a,b,c,x1,x2,D;
* ** * * *** **** ** * ** * * * %f ** * * ** * *
*** * * **** * **** * * * * ***
** * * * ** **** = (-b + sqrt(D))/(2*a);
*** **** ** * * * * ** = (-b - sqrt(D))/(2*a);
** * *** ** **** ** * ** ******
* * * ** *** ** *** * * * ** * *
** *** * ** ** ** ** ****** * *** **** ** * ** * ** * * ** **** of %.2fx^2 + %.2fx + %.2f = 0 are real and different\n",a,b,c);
* * *** * ** ** * * ** * ** * * **** * ** ****** ** * *** ** ****** ** = %.2f\n",x1);
* * ** ** *** ****** *** *** *** **** * * * *** * * * ** * **** * * * * * = %.2f",x2);
* ** ********* *** * * * * *
* * * * * * **** * * if(D==0)
* * ** * **** * ****** **** ** ** * *** ***
* * **** ** * * * *** **** ** * * ** ***** * * * ** ** * ** * ** *** *** *** *** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\n",a,b,c);
** * * * * * * ** ** * ** ** * * * * ** ** * * * ***** * *** * * * * * **** = x2 = %.2f",x1);
** * * * * ** * * * *** * * *
**** ** * * * ** * ***
**** ** * **** * ** * * * ** *** * * * ***
*** ****** *** * ** * *** * * * * * * *** ***** * ** * *** * * * ** ** of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\n",a,b,c);
* ** ** * * ** ** ** * * * *** * ** * *** **** * * * * * * * * ** * * = * **** ******** * *** ** **
* * * * **** * * * * *** ** * ** * *** * * * * ** *** * * * = * * *** **** * * *** *
** ** * ** ** *** ***** * *** *** ****
* ** * **** **** 0;
}
answered by (-258 points)
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
0 like 0 dislike
Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include<math.h>
int main()
{
** *** * *** * * * * a,b,c,x1,x2,D;
* *** * ** * ** * ** * *** * *** %f * **** * ** * * ***
* * * ** * ** ***** * * ***
** * * * *** * *** * * * = (-b + sqrt(D))/(2*a);
* ** * ** ** ** * ** ** = (-b - sqrt(D))/(2*a);
* ** *** *** * ****** ** * *****
* ** * * ** * * * * * ** ** ** ***** ****
** * ** * * **** * * * ** ** ** ** * **** * * *** ** * *** ** * * ** * * of %.2fx^2 + %.2fx + 1.00 = 0 are real and different\n",a,b,c);
** ** * * ** * * * ******* * * **** * * * * * * * ** **** * **** * = %.2f\n",x1);
** **** * * * ** * * ** ** ** ** * ** * ** ***** * * * * *** ** ** * *** = %.2f",x2);
* *** * **** * * * * * * ***** * * * *
* ** * * *** ** ** * ** * * * if(D==0)
*** *** ** * * ** * * ** ***** **** * * * **
* * ** * ** ** * ** * * * ** ** * ** *** *** * *** * * *** *** * ** * * * * of %.2fx^2 + %.2fx + 1.00 = 0 are real and same\n",a,b,c);
** **** **** * * ** *** * * * ** * *** * ** * ** * * ** * * * **** = x2 = %.2f",x1);
*** ** ** * * ** * *** * * * *** ** *
* ******* ** *** * *** * ***
* * * * * * * * * * * *** *** **** *
* * * **** * * **** **** * ** ** *** ** * * *** * * *** * of %.2fx^2 + %.2fx + 1.00 = 0 are complex and different\n",a,b,c);
* ** ** * ** ** **** * *** **** **** * ** ** * ** *** ** *** * * ** * * = * *** *** ** * ***** ** *
** * ** **** *** * *** * * * ***** ***** *** ****** * ** **** * ** *** **** * ** = * *** * * ***
******** ** ** * ** ** *** * ** * * *** ** *** * ** *
** * * *** * * * * * 0;
}
answered by (-258 points)
0 0
prog.c: In function 'main':
prog.c:13:20: warning: too many arguments for format [-Wformat-extra-args]
             printf("Roots of %.2fx^2 + %.2fx + 1.00 = 0 are real and different\n",a,b,c);
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:19:20: warning: too many arguments for format [-Wformat-extra-args]
             printf("Roots of %.2fx^2 + %.2fx + 1.00 = 0 are real and same\n",a,b,c);
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:24:20: warning: too many arguments for format [-Wformat-extra-args]
             printf("Roots of %.2fx^2 + %.2fx + 1.00 = 0 are complex and different\n",a,b,c);
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0 like 0 dislike
Hidden content!
** *** ***********
**** ** *** * **
int main()
{
*** ** * * * * ** ** ****** a,b,c,D = 0,x1 = 0,x2 = 0;
* * * **** * ** ** **** *** ** **** ** * * ** **** ******

* ** *** *** * ** *** ***** * * of %.2fx^2 + %.2fx +%.2f = 0 **** * * **
* * * ******* ** *** = (b*b-4*a*c);
* * * **** * * ** * * (D < 0)
** * * ** * ** * * * *
* *** *** * *** * **** ** * complex and ** * **
** * ** **** ***** ** * ****** ** = *** ** * * * ** * *
** ** *** ** * ** ** * * * = ** ** ** ** * *
* * ** ** * *** * *
** * * *** * * *** (D > 0)
* **** ** * ** * **
** **** ** * * * * * ** real and * **** **
** *** * * * ** *** *** ** * = * * * * * + sqrt(D))/(2*a));
* * ** *** * *** ** **** ** * ** = %.2f",(-b - sqrt(D))/(2*a));
* * ** * *** * ** ** ****
*** * ** * * ** * (D == 0)
**** ** **** * ** * ** * * *
** ***** * ** ** * *** * ** * real and same\n");
** * ** ** * = x2 = %.2f",(-b + sqrt(D))/(2*a));
*** *** ** ** *********
}
answered by (-214 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
your output lack of 1 space at line 8 when print out "Roots of ..."
0 like 0 dislike
Hidden content!
***** * ** ** ** * *
*** ********** ** **
int main()
{
** ** * ** ** ** a,b,c,D = 0,x1 = 0,x2 = 0;
* ***** **** * *** ** ** *** ** ** ** *** * *** * * *

*** * * *** **** *** * * ** of %.2fx^2 + %.2fx +%.2f = 0 * ** ******* *
* ** ** * * ** * * * = (b*b-4*a*c);
* ** * ** ****** ** *** (D < 0)
** * *** * *
* ** ** ****** * * ** **** ***** * complex and * ** ** ** *
* *** * ** ** * *** ***** * = ** **** ****** * *** ***
* ** ** *** * * ** ** * ** * ** **** = *** * * * * * *** * ** *** **
*** ** * * ** * * ** * *
* ** * ** * * * ** * * (D > 0)
*********** **** ** **
** * * * * *** ** ***** ** ** * * ** real and * * * *
* * * ** ** *** ** * * ** * = **** * * + sqrt(D))/(2*a));
* ** ** ** ** *** ***** * * = %.2f",(-b - sqrt(D))/(2*a));
**** **** *** **** **
* * *********** *** (D == 0)
** *** ** *** *** ***
*** *** * * ******** * * ** * * * ** * real and same\n");
* ** * ** ****** * * *** * * * * * = x2 = %.2f",(-b + sqrt(D))/(2*a));
* * ** * **** * **** * * *
}
answered by (-214 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 like 0 dislike
Hidden content!
*** * ***
**** ** * * *
int main()
{
** ********* ** * * * a,b,c,D = 0,x1 = 0,x2 = 0;
* ***** *** * * *** * ** * *** * ** * *

** * * * ** *** * ** * * ** ***** ** of %.2fx^2 + %.2fx +%.2f = 0 * ** ** * * *
* ** ** *** * * ** * * ** = (b*b-4*a*c);
** * ** * ** * ** * (D < 0)
* * * ** * *****
** * *** *** **** * ***** * ***** complex and ****** ** *
** * * ** * * *** * ***** = * ** * ** * ** * ** * *
*** ** *** * * * * * ****** * = ** ** *** *** ** * ** ** * **** *
** * ***** ** **** *
** ** * * ** (D > 0)
** ** * * * ** *** **** *
* * ** * *** * ** * * real and ** *****
*** * ** ** *** *** *** ** * = **** * * *** + sqrt(D))/(2*a));
** **** * * * ** ***** ** ** * * ** = %.2f",(-b - sqrt(D))/(2*a));
** * * * * * * * * *
* ****** **** * * * * (D == 0)
* * *** * ******* *** *
* * * *** * ** ** ** * * real and same\r\n");
** * ** ****** * * * *** *** * = x2 = %.2f",(-b + sqrt(D))/(2*a));
* ** * * ****** *****
}
answered by (-214 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 like 0 dislike
Hidden content!
* * * **** ** * *
** **** *** **
int main()
{
** **** * ** **** ** a,b,c,D = 0,x1 = 0,x2 = 0;
* *** * ** * * * * ** ** *** * * *** * ** ** ***** **** ** ** * ***

* * ***** * ** ** * ******* * of %.2fx^2 + %.2fx +%.2f = 0 ** * *** ** * *
** * * * *** ** * * = (b*b-4*a*c);
* ** * * * * *** ** * ** (D < 0)
***** * **** **** ** ***** **
** * *** ***** * * ** ** * * ** * * complex and **** * ** * **
******** ****** **** * * ** ** * ** * ***** = ** ** ******* *** ** *** *
* ***** ** **** ** *** ** * * = *** * * **** * * ** *
** *** * * * * ** **
* **** ** * * * ** * * * (D > 0)
* ** *** *** ****
* * ** * * * * * ** ***** **** ** * * real and * * * * *
* * * * *** * * ** * * *** ** ** = * * **** + sqrt(D))/(2*a));
****** * * **** * ***** * *** * = %.2f",(-b - sqrt(D))/(2*a));
**** * **** * * * *
* * *** ***** * **** (D == 0)
**** *** ** * * * **
* * ** ****** * * * *** ** * *** * real and same\r\n");
* * ** ** * **** * * * *** ** = x2 = %.2f",(-b + sqrt(D))/(2*a));
* ** * ** * * *** ** * *
}
answered by (-214 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 like 0 dislike
Hidden content!
* ** * * * * *
* * ** ** ** **
int main()
{
** ** * * * * ** *** * * a,b,c,D = 0,x1 = 0,x2 = 0;
* *** * **** *** * ** * * ** * ** *** *** * ** *** **

*** * ** **** ** **** *** * * * * of %.2fx^2 + %.2fx +%.2f = 0 are",a,b,c);
** *** * *** ** * ** * = (b*b-4*a*c);
* * ***** *** * * ** = (-b + sqrt(D))/(2*a);
*** * **** * * * * * = (-b - sqrt(D))/(2*a);
* **** **** * ** * ** (D < 0)
* * ****** * * ***
* **** * ** * ** **** * * complex and *** ** ***
*** * *** * **** ** *** ** ***** = *** ** * ***** ** * **
*** *** ***** ** *** ** * ** = * * * * *** * *** ** *
* ***** ***** ** * * *
*** **** * * ***** (D > 0)
* * * ** * ** * * ** *** **
* * *** *** ** * * * *** * **** real and * ***** * * **
**** ** * ** *** * ** **** = *** ** * * *
*** **** *** * **** ** = %.2f",x2);
** * * * *** **** * ****
** * *** ** * **** *** ** ** (D == 0)
** ** *** *** * *
** ** ** * ** ** ** * ** * * real and same\r\n");
* * * * *** ** * ** * ** *** *** * = x2 = %.2f",x1);
* ** * * * *** ** **
}
answered by (-214 points)
0 0
Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
Welcome to Peer-Interaction Programming Learning System (PIPLS) LTLab, National DongHwa University
English 中文 Tiếng Việt
IP:172.69.130.53
©2016-2025

No related questions found

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