0 like 1 dislike
8.6k 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 | 8.6k 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!
#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:172.69.17.63
©2016-2025

No related questions found

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