0 like 1 dislike
12.1k 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 | 12.1k 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:172.69.17.66
©2016-2025

No related questions found

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