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:172.69.6.172
©2016-2025

No related questions found

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