0 like 1 dislike
12.1k 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 | 12.1k 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:172.70.126.9
©2016-2025

No related questions found

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