62 lines
1.3 KiB
C
62 lines
1.3 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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// This function will return
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//
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// 0 if the equation can be solved,
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// -1 if it is not a quadratic
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// -2 if it is complex
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int SolveQuadratic ( int a, int b, int c, float *x1, float *x2)
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{
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int d;
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// If the equations is not a quadratic return -1
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if ( a == 0 )
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return (-1);
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// Calculate the value that will be square rooted
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d = (b*b) - (4*a*c);
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// If less than zero then it would be complex - give up!
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if ( d < 0 )
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return (-2);
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// If we got to here we are OK to solve things
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*x1 = (-b - sqrt(d)) / (2*a);
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*x2 = (-b + sqrt(d)) / (2*a);
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// This is are 'OK' return value
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return 0;
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}
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int main()
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{
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int A,B,C, r;
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float X1, X2;
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printf ("Please enter a b & c separated by a space: ");
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scanf("%d %d %d",&A, &B, &C);
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r = SolveQuadratic(A,B,C, &X1, &X2);
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// The value returned lets us know if we have values in X1 and X2 we can use
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switch (r)
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{
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case 0 :
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printf ("The solutions are %f and %f", X1, X2 );
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break;
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case -1 :
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printf ("The equation provided was not a quadratic" );
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break;
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case -2 :
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printf ("The solutions had complex roots and could not be solved");
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break;
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}
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return 0;
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}
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