0 like 1 dislike
9.1k 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 | 9.1k 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:172.69.6.217
©2016-2025

No related questions found

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