0 like 1 dislike
9.4k 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 | 9.4k 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!
#include <stdio.h>
* ** * ***** **
int main()
{
* *** * ** ** ** * ** ** * * ** * ** * * ***
* **** * ** * ** **** * *** * * %f * *** * *** * ** **
*** ** *** * * * = (b*b-4*a*c);
** ** ***** * **** = (-b + sqrt(D))/(2*a);
* * * ** * ** *** * = (-b - sqrt(D))/(2*a);
** ****** ** ** ** ** * * ******* = -b/(2*a);
** ** * * * * * * ** * ** =sqrt(-D)/(2*a);
** * ** * * * * * * **
* *** ** *** * * *
* **** ** * *** * * * *** * *** * **** * * of %.2fx^2 + %.2fx + %.2f = 0 are real and * ** ** * *** *
* * * * * ** ****** ** ** * ** ** = %.2f\nx2 = %.2f",x1,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 ****** **
**** *** ***** * ******* * *** * * *** * * * *** * = ** ** *** * * *** *
* * *** * ** * * ***** * ** * ** * * * ** *** * * * * *** = * *** ** * ** * ** * * * *
* **** **** * * *
* * * ****** * ** ** ** 0;
}
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 ** * **

int main()
{
** * * **** * * ** * * n, i;

*** * ******* ****** ***** *** **** * &n);

*** * **** *** *** ** * * * = 1; i <= n; ++i)
* * ** ** ** * **
* ** **** * *** * ** * * * ** **** ** * ** % i == 0)
*** ****** ** * *** * **** ** *** *** **** ** ** ** **** * * ****** * *** * ** ** ", i);
* *** ** *** *** *

* * ***** ****** * * * * 0;
}
answered by (-284 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()
{
* * *** * ** ** ** * * ** * ** * ****
* * **** * ** * *** * ** * **** * * * * * * * ** * ** * * ** *
**** * * * ** * *** ** = ** *
* ** ** ** * * *** * * **
* ** ** * * ** ** * * *
* ** **** * * **** ** * * ** *
** * * ** * * **** = -b /(2*a);
** **** * * ** *** * * ** ******* ***
* ** * **** ** = (-b)/(2*a);
** * * ** **** * *** * * * ** * * of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\nx1 = %.2f+%.2fi\nx2 = *** * * * * * * ** *** *
****** ** ***** * ** *
** * ** * * ****** if(D==0)
** ** ** ** ** *****
* *** * ** **** *** * = (-b + ***** * *
* **** * * * * * ** * = (-b - *** ** *
*** * * * * ** ** * **** ** **** * * of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = * ****
*** * ** *
* * * * **** *** * * ** ** if(D>0)
* ** * * * * * * *
* * * ** * **** ***** * = -b/(2*a);
* * ****** ** ** * = (-b + ** **
* ** ****** * ** *** * = (-b - ** * **
**** * * * * *** * ** * * ** * ** * of %.2fx^2 + %.2fx + %.2f = 0 are real and different\nx1 = %.2f\nx2 = * *** ** **
*** ** *** **** **
* ** ** **** ** * ** ** * 0;
}
answered by (-323 points)
edited by
0 0
Case 0: Correct output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output
Case 3: Wrong output
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()
{
* *** * * * * * a,b,c;
**** * * **** ************* * ***** * ** ** *** **** * ** ****
** ** * * ***** ** ** *
* ***** * *** * * ** * ** *** * *
*** * *** ** *** ** ** *
** *** *** **** *** *** ********** * *** * * * * * ******* of %.2fx^2 + %.2fx + %.2f = 0 are real and different\nx1 = %.2f\nx2 = *** *** * + * ****** * ** - *** * ******* ***
* *** *** * * * ****
** *** **** *** *
***** ** * ***** ** ** **** if (b*b-4*a*c==0)
* ** * * ** * ** * ** **
***** *** ** * * * ** * ** * * * ***** * **** * **** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = ** ** **** * + * * *
* ****** ** * *
* * * * *********
* * ** ** ***** * **
** * * * * * * * ******
* * * ** * * * ** * * ** ** * **** ***** * * **** *** of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\nx1 = %.2f+%.2fi\nx2 = * * * * * * * * * *** * *** * ****** ***** ** **
* *** **** * * * **
* * **** * *** ** * * * 0;
}
answered by (-127 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 * * ** * *
#include **** *** *
int main()
{
****** ***** * * * *** ** a,b,c;
* ** ** * * * *** ** ** *** ** * *** ** ** * * *
* * *** ** * ***
*** ** * *** *** * * ** * ***
* * * ** * * *
* ** * ******* ** * *** ***** ******* * *** ** **** *** * * of %.2fx^2 + %.2fx + %.2f = 0 are real and different\nx1 = %.2f\nx2 = ** ** * * ** + *** * * - ** **** *
** *** ** * * ** ****** * ***
* *** * * ** ** * *
****** ******** *** ** * * * if (b*b-4*a*c==0)
** *** * ** ***** * *
******* * * * ** *** * ** ** * * * * *** ** of %.2fx^2 + %.2fx + %.2f = 0 are real and same\nx1 = x2 = ** *** *** + * * ** ****
** * * ** * ***
* * **** * * * * **
* ** ** * *** ** * ** *** * *
*** * * *** ** ** *
* ** **** ** ** ** * * ** ** *** *** ** *** * *** of %.2fx^2 + %.2fx + %.2f = 0 are complex and different\nx1 = %.2f+%.2fi\nx2= ** ** ***** * *** ** * ***** *** * ** *** *
** *** * ******
**** ***** * *** * ***** 0;
}
answered by (-127 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,d,x1,x2;
** *** * * * *** * **** ** * ****** ** ** **** * * ** *
***** * ** ** ** * ** * * ***
*** ** ** * * * *** * **** * ****
* ****** * ** *** *****
*** * * * * ******* ** *
**** * **** ****** ** * **
* *** * ** * * ** * * * ** **** ********** ****** * of %.2fx^2 + %.2fx + %.2f = 0 are real and *** ** * **
**** * * ***** **** * *** * ** *** * ********* *** ** = %.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 ** *** * * ******
* * *** ** ** ** ** *** * ***** ** * * ** ** ***** = *** ***** ** * * ***** *****
* ***** *** *** * ** * *** * * *** ** *** * **** ** ** * = * * **** ******* * ** *
* ***** ** * ***
* ** * * *** ** *** ** ** 0;
}
answered by (-214 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!
int a, b, c, D, spD, x1, x2;
* **** * * * ** ** **** * * * * *** ** *** * * * * * aX^2 + bX + c = 0\n以a b c表示\n");
    while(scanf("%d %d %d", &a, &b ,&c)==3){
** * * * ** *** ** * * * **** *** - (4*a*c);
*** ** *** *** ** * * ******* ** * * * * *** *
***** **** ** ** * * * * ** ** **** * * ** ** * *** * * * **
* *********** * **** *** ** ** ** * * * ** * *** ****** ** ** * (-b+spD)/(2*a);
** * ***** **** * * ** * * **** * ** * ** ** * * ** * *** ********* (-b-spD)/(2*a);
* ** * *** * * * ** * ** ** ******** * * ***** * **** ** * * (x1==x2){
* *** * * * ** * * * ** * ** **** *** *** * ** * * *** * ** ** * ***** ** **** *** **** * * * ** * * * **** X=%d\n", x1);
** * ** *** *** ** ** *** ** * * * * ******* * **** **** **
* *** * * * * **** ** * * * * **** ** * *** * * ** *** * {
* **** * ** *** * ** ** ** ** *** *** ** ** * ** * ** * ** ****** ** **** *** ** ** * * *** * * *** *** X=%d或%d\n", x1, x2);
* ***** * *** ********* * * * ***** *** ** * * * * *** *** ***
        }
*** ** ** ** ****** *** * **** *** ** ** ** ** * if(D==0){
** ** ** **** * ** ********** *** * * * ***** * * *** ************** **** * (-b)/(2*a);
** * * ******** * * ** ** * *** * * *** ** ** * *** * *
*** ** * * * * *** ***** *** ***** * * ** ** ** ** *** *** * * * * * ** ** **** * * * ****** * * X=0");
* * * ** * * * * * * **** * * * * ** * ** * * * *** * ** ** *
* * * * * * ** * * * * **** ***** ** * * * ** **** * * ** *** ** * *
**** * ** ** * * *** * * * * ** ** * **** * * *** * * * * ** * ** ** *** * * ** *** X=%d\n", x1);
* ** * * *** * *** **** ** * ** *** * ** ** **** *** *** * * *
        }
* * ****** *** *** * * *** * * **** * ***
** ** **** *** * ** * ** * ** *** * **** * ** * * * ** * * ***** ** ** * ** * * ****
* *** * * * * * * *** **** * *** ** ** *** * * **
    }
* * **** * **** * ***** * *** * * * * * ** ** * *** **
    system("PAUSE");
    return 0;
}
answered by (-32 points)
0 0
prog.c:2:12: error: expected declaration specifiers or '...' before string constant
     printf("\xe8\xab\x8b\xe8\xbc\xb8\xe5\x85\xa5\xe4\xb8\x80\xe5\x85\x83\xe4\xba\x8c\xe6\xac\xa1\xe6\x96\xb9\xe7\xa8\x8b\xe5\xbc\x8f\xe7\x9a\x84\xe4\xb8\x89\xe5\x80\x8b\xe4\xbf\x82\xe6\x95\xb8\xef\xbc\x8c\xe5\xa6\x82 aX^2 + bX + c = 0\n\xe4\xbb\xa5a b c\xe8\xa1\xa8\xe7\xa4\xba\n");
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:3:5: error: expected identifier or '(' before 'while'
     while(scanf("%d %d %d", &a, &b ,&c)==3){
     ^~~~~
prog.c:29:12: error: expected declaration specifiers or '...' before string constant
     printf("\xe8\xab\x8b\xe8\xbc\xb8\xe5\x85\xa5\xe6\xad\xa3\xe7\xa2\xba\xe7\x9a\x84\xe4\xb8\x89\xe9\xa0\x85\xe4\xbf\x82\xe6\x95\xb8");
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:30:12: error: expected declaration specifiers or '...' before string constant
     system("PAUSE");
            ^~~~~~~
prog.c:31:5: error: expected identifier or '(' before 'return'
     return 0;
     ^~~~~~
prog.c:32:1: error: expected identifier or '(' before '}' token
 }
 ^
0 like 0 dislike
Hidden content!
#include <math.h>
#include <stdio.h>
#include <stdlib.h>

int main ()
{
* * * ** ** * * *** * a,b,c,D;
*** * **** ** ** * * * * x1,x2;
* *** * *** ******* * ** * %d * * ** ** * *** **

***** ***** * ** ***** ***
*** * * ** **** * *** ***** *** *
* * * *** * * * ** * * * * * * ** *

** ** ** * * ** * A,B,C;
** * **** * **** * * ** **

* ** * *** * ***** * **** *
* ** ** ** * ****** * * * * **** ** ***** ****** ** ** * * * of %.2fx^2 + %.2fx + %.2f = 0  are real and * **** **** * ***
* * * * * * * * * * * * * * ** ** *** ** *** *** * * = %.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);}

* * *** * * * * * ** * if(D<0)
* * * * * * * *** ** ** ** ** ** * ** *** ** of %.2fx^2 + %.2fx + %.2f = 0  are complex and **** * *** * ** * *
**** **** ** * * ** **** * * *** * * * ** * * bb,d,dd;
* ** ** ***** ** * * ** * * ** * * * * * ***** ****
*** * * *********** * * ** ** * * * ** * ** * * ** * * *** ** **
** * **** ***** * ** * **** ** ** ******** ** ******* * ** * **** * = * * * **** *
**** * * *** * * * * * * * *** ** * * *** * ** ** ** ** = * * ** * ** **

**** **** *** * ** *** 0;
}
answered by (-16 points)
0 0
Case 0: Correct output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 0
Case 0: Correct output
Case 1: Wrong output
Case 2: Wrong output
Case 3: Wrong output
0 like 0 dislike
Hidden content!
#include <stdio.h>
* * ** * ****
int main()
{
* * * * * * *** ** * * * **** ***
** * * ** * * * ** * **** * * %f ***** * * ** * * *****
* ** * * ** * ** = (b*b-4*a*c);
* * * * * * * ********* = (-b + sqrt(D))/(2*a);
** *** ** **** **** ** ** = (-b - sqrt(D))/(2*a);
* * * * ** **** ** * * ** = -b/(2*a);
* ** * *** * ** * ** * * =sqrt(-D)/(2*a);
* * * * * * **** ** ***
*** * **** * ** * ***** **
* * ***** * ** **** ** ** * * * * ***** ** * * * * of %.2fx^2 + %.2fx + %.2f = 0 are real and * *** *** *
*** * **** * *** **** * *** **** ** ** * ** * = %.2f\nx2 = %.2f",x1,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 * ** ** *
* ** ** *** ** ** * *** ** ** * ** * * * * * = * ** *** * **** **
** *** *** * *** ** ****** **** * * * ***** * * * * * * * * * = ** ***** * ** ******* **
* ****** * * ** *** ** **
*** ** * ** * * **** * * 0;
}
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 <stdio.h>
** * * * *
int main()
{
* * * * *** ** * * * * *** ** *** ** * ** **
** ** ** * * **** **** *** *** ** %f ** * * * **** ** * **
** * ***** * **** *** * = (b*b-4*a*c);
* * * * * * *** * * = (-b + sqrt(D))/(2*a);
*** * **** *** ** *** * * = (-b - sqrt(D))/(2*a);
* * * ** ** ** * = -b/(2*a);
* * * * **** ** * ** =sqrt(-D)/(2*a);
** ** *** **** * ** * * *
* ***** ** ****** *
***** ** * * * * * *** ** ** ** * ****** * * * * * * of %.2fx^2 + %.2fx + %.2f = 0 are real and * ** ** ** * * ** **
*** * * * *** * * *** * * ** * * * ***** * * * * = %.2f\nx2 = %.2f",x1,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 * * * ***
*** *** ** ** ** * * ** ** * * ** * ** **** * = * ** * * * * ****
**** * *** *** ** ** * ** ** * * * * * * * ** ** * ** * *** = ** * **** *** ** * ***
*** * * * ** ** ** *
** ** * **** ** * * ** 0;
}
answered
0 0
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output
Case 3: Correct output
Welcome to Peer-Interaction Programming Learning System (PIPLS) LTLab, National DongHwa University
English 中文 Tiếng Việt
IP:172.70.130.233
©2016-2025

No related questions found

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