48 lines
1.0 KiB
C
48 lines
1.0 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h> // Needed to give access to M_PI
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/* FUNCTION: CalculateAreaOfCircle
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INPUTS: radius float
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RETURNS: area float
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Description
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Calculate area using area = M_PI * radius * radius
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*/
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float CalculateAreaOfCircle ( float radius )
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{
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float area;
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area = M_PI * radius * radius ;
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return (area) ;
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}
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/* Show use of function */
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int main (void)
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{
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// Declare variables - no need to initialise as values will be read in / calculated
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float rad, Area;
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// Prompt for and obtain value
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printf ("Please enter the raduis of the circle: ");
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scanf ("%f", &rad);
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// Use our function to calculate the area
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Area = CalculateAreaOfCircle(rad);
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// And display the answer on the screen
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printf ("The area of a circle of radius %f is %f\n", rad, Area );
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// Note: As the function returns a value, if we did not need to store it
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// we could calculate & display within the printf statement
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//printf ("The area of a circle of radius %f is %f\n", rad, CalculateAreaOfCircle(r) );
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// All done
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return 0;
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}
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