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:172.69.17.59
©2016-2025

No related questions found

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