0 like 1 dislike
7.6k 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 | 7.6k 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:172.70.126.200
©2016-2025

No related questions found

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