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:172.70.194.138
©2016-2025

No related questions found

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