[Courses] [C] Beginner's Lesson Three: Answers to Exercises

[KWMelvin]

Greetings,

Here are my answers to the exercises from lesson 3.
I have limited myself to using only the information
presented in the lessons to date, so these answers
may not be how a professional C programmer would
solve these problems.  

I found an error in these exercises:

In Exercise 3, the formula for the circumference of
a circle should be: Circumference = 2 * pi * radius
I'm sorry.

/* exerciz1.c -- output name, birthday, fave ice cream */
#include <stdio.h>
int main(void)
{
	printf("My name is KWMelvin.\n");
	printf("My birthday is 23 August.\n");
	printf("My favorite ice cream is \"Mexican Vanilla\".\n);
	return 0;
}

/* exerciz2.c -- output block 'F' 8x6 using #'s */
#include <stdio.h>
int main(void)
{
	printf("######\n");
	printf("##\n");
	printf("##\n");
	printf("######\n");
	printf("##\n");
	printf("##\n");
	printf("##\n");
	printf("##\n");
	return 0;
}

/* exerciz3.c -- compute area and circumference of circle  */
/* Area formula: A=pi*r^2 ------  Circumference: C=2*pi*r  */
#include <stdio.h>
int main<void>
{
	/* variable declarations */
	float pi = 3.14159;  /* rounded-off value for pi         */
	double radius = 6;   /* diameter is 12 so radius is 6    */
	double area = 0;     /* initialize area to zero          */
	double circum = 0;   /* initialize circumference to zero */

	/* calculate the area */
	area = pi * radius * radius;

	/* calculate the circumference */
	circum = 2 * pi * radius;

	/* Output area and circumference of circle */
	printf("The area is %f\n", area);
	printf("The circumference is %f\n", circum);
	return 0;
}

What changes have to made to output the area and circumference
for a 12.5 feet diameter circle?
Change the line 
	double radius = 6;  
to 
	double radius = 6.25;


/* exerciz4.c -- print your name in 7x5 block letters */
#include <stdio.h>
int main(void)
{
	printf("K   K  W   W  M   M\n");
	printf("K  K   W   W  MM MM\n");
	printf("K K    W   W  M M M\n");
	printf("K      W W W  M W M\n");
	printf("K K    W W W  M   M\n");
	printf("K  K   WW WW  M   M\n");
	printf("K   K  W   W  M   M\n");
	ireturn 0;
}

/* exerciz5.c -- mistakes */
#include <stdio.h>
int main(void)
{
	float flt = 1.0;
	int num = 2;
	char chr = 'a';

	printf("%d\n", flt);
	printf("%f\n", num);
	printf("%d\n", chr);

	return 0;
}

Output:
	0
	1.000000
	97

Happy Programming!
--
K