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:172.69.214.204
©2016-2025

No related questions found

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