0 like 1 dislike
12.2k 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 | 12.2k 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:172.69.6.173
©2016-2025

No related questions found

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