Sample Midterm

1.	What are all possible outputs of the following code fragment?

void f(int a, int b)

{

		printf("%d %d\n", a, b);

}



void main(void)

{

		int i = 5;

		f(++i, ++i);

}

2.	Given the definitions

		int numbs[10];

		int *ptr = numbs;

	which of the following are equivalent, and why?

a.	numbs[3]

b.	numbs + 3

c.	* ( numbs + 3 )

d.	* ( ptr + 3 )

e.	*ptr + 3

3.	Write a recursive function to add the integers from a to b.  You may assume that a  b initially.

4.	Use the following code fragment to answer parts a, b, and c:

for(x = i = 0; i <= 100; i += 2, x += i);

a.	In one short sentence , what does this for loop do?

b.	Is the following while loop equivalent?  If not, how does its result differ?

		x = i = 0;

		while( i++ = 100)

			x += ++i;

c.	Does the following for loop do the same thing?  If not, what does it do?

		for(x = i = 0; i <= 100; i++){

			if (!(i % 2))

				continue;

			x = x + i;

		}

5.	What does the following function do?

		int x(char *s, char *t)

		{

			for( ; *s == *t; s++, t++)

				if (*s == '\0')

					return(0);

			return(*s - *t);

		}

6.	What does this function do?

char *x(char *s, char c)

{

		char *r = NULL;



		do{

			while(*s && *s != c) s++;

			if (*s) r = s; 

		} while(*s++);

		return(r);

}

7.	The following segment of code is supposed to print the number of times the routine a_again is called.  Yet, 
regardless of the input, it prints 0.  Why?  How would you fix it?

void a_again(int acount)

{

		++acount;

}



void main(void)

[

		register int c;

		int counter = 0;



		while((c = getchar()) != EOF)

			if (c == 'a' || c == 'A')

				a_again(counter);



		printf("%d\n", counter);

		exit(0);

}