Simple C Programming Questions

Please answer parts A through L. Some are True or False others are multiple choice questions. No programming necessary just answer the 10 parts (A through L) to receive Positive score. If any are skipped, I will rate negatively. I have attached Problem34.c and its sample output if you need it to answer the questions.

PartA.

T or F? stdout is a macro defined as a pointer-to (the main memory address-of) the 1^st element of (at index 0 of) an array-of FILE variables.

PartB

(Continuing 1) T or F? sizeof(FILE) is 20₁₆ = 32₁₀.

PartC

(Continuing 1) T of F? FILE is the name of a struct type.

PartD

(Continuing 1) How many elements does an object or instance of a FILE type contain?

A: 1 B: 2 C: 4 D: 8 E: none of these

PartE

The essence ofbut not exact syntax that you will find forthe function prototype for printf() (that is also found in ) is

int printf(const char *, ...);

How many actual parameters can be passed to printf()?

A: always exactly 1 B: always exactly 2 C: 2 or more D: 1 or more E: none of these

PartF

The displayed addresses of the functions main(), F(), UnusedFunction1(), and UnusedFunction2() are very close to one another. How close, measured in bytes, are the closest 2 addresses? A: 15₁₀ B: 9₁₀ C: 5₁₆ D: 4₁₀ E: none of these

Note The displayed addresses of the functions are too close to represent the actual address-of the first instruction of the body of each function because the function bodies must be larger than the few bytes that separate them. Dr. Hanna suspects what we are actually looking at is a table of starting addresses.

Part G

The global constant F1 (whose main memory address is 0042301C₁₆) and the literal string constant "n? " (address 00423064₁₆) are only 48₁₆ or 72₁₀ bytes apart, so, Y or N? is it reasonable to assume they are stored in the same area of memory?

PartH

(Continuing 8) The global constant F1 is separated from the global variable calls (address 00426794₁₆) by 3778₁₆ bytes of memory. How many full (do not include partial) 1K-byte memory pages is 3778₁₆ = 0011011101111000₂ bytes? Note The displayed addresses of F1 and calls are probably not close enough to be considered in the same area of main memory.

A: 37₁₆ B: 37₁₀ C: 13₁₀ D: 14₁₀ E: none of these

Part I

The variables n, i, Fn, and totalCalls are local variables defined in the function main() that are automatically-allocated in the activation record for main() when main() is activated (when it is called by the operating system and becomes active). The variables occupy contiguous memory locations in the activation record. The activation record is on the run-time stack. How big is each of the variables? A: 1 byte B: 2 bytes C: 4 bytes D: 8 bytes E: none of these

Part L

The value of the variable calls before it is initialized is an indeterminate piece of RAM garbage, but the value of calls after it is initialized with the malloc() function return value is a main memory address that points-into which area of main memory? Hint See line 154!

A: the run-time stack (see Question 10) B: the global constant area (see Question 8)

C: the function address table (see Question 7) D: the heap E: none of these

//---------------------------------------------------

// Problem #34

// Problem34.c

//---------------------------------------------------

#include

#include

#include

#include

#define TRACESTACK

#define F0 0

const int F1 = 1;

int *calls;

//---------------------------------------------------

int main()

//---------------------------------------------------

{

int F(int n);

void UnusedFunction1(void);

void UnusedFunction2();

int n;

fprintf(stdout,"n? ");

while ( fscanf(stdin,"%d",&n) != EOF )

{

int i,Fn,**totalCalls;

calls = (int *) malloc(sizeof(int)*(n+1));

totalCalls = (int **) malloc(sizeof(int *));

*totalCalls = (int *) malloc(sizeof(int));

printf(" 1) stdout = %p ",stdout);

printf(" 2) stdin = %p ",&*stdin);

printf(" 3) sizeof(FILE) = %X ",sizeof(FILE));

printf(" 4) &main() = %p ",main);

printf(" 5) &F() = %p ",F);

printf(" 6) &UnusedFunction1 = %p ",UnusedFunction1);

printf(" 7) &UnusedFunction2 = %p ",UnusedFunction2);

printf(" 8) &F1 = %p ",&F1);

printf(" 9) &calls = %p ",&calls);

printf("10) &n = %p ",&n);

printf("11) &i = %p ",&i);

printf("12) &Fn = %p ",&Fn);

printf("13) &totalCalls = %p ",&totalCalls);

printf("14) calls = %p ",calls);

printf("15) &calls[0] = %p ",&calls[0]);

printf("16) &calls[n] = %p ",&calls[n]);

printf("17) totalCalls = %p ",totalCalls);

printf("18) *totalCalls = %p ",*totalCalls);

printf("19) **totalCalls = %10d ",**totalCalls);

printf("20) &\"n? \" = %p ","n? ");

printf("21) &\"n? \" = %p ",&"n? ");

printf("22) &\"%%d\" = %p ","%%d");

for (i = 0; i <= n; i++)

calls[i] = 0;

Fn = F(n);

printf("F(%2d) = %10d ",n,Fn);

**totalCalls = 0;

for (i = 0; i <= n; i++)

{

**totalCalls += calls[i];

printf(" F[%2d] called %10d times ",i,calls[i]);

}

printf(" ============================= ");

printf(" Total calls %10d times ",**totalCalls);

free(calls);

printf("23) calls = %p ",calls);

printf("24) calls[n] = %10d ",calls[n]);

free(*totalCalls);

printf("25) *totalCalls = %p ",*totalCalls);

printf("26) **totalCalls = %10d ",**totalCalls);

free(totalCalls);

printf("27) totalCalls = %p ",totalCalls);

printf("28) *totalCalls = %p ",*totalCalls);

printf(" n? ");

}

system("PAUSE");

return( 0 );

}

//---------------------------------------------------

int F(int n)

//---------------------------------------------------

{

calls[n]++;

#ifdef TRACESTACK

{

char *memoryLeak = (char *) malloc(sizeof(char));

double *mallocThenFree = (double *) malloc(sizeof(double));

assert( memoryLeak != NULL );

printf(" n = %2d, &n = %p, memoryLeak = %p, mallocThenFree = %p ",n,&n,memoryLeak,mallocThenFree);

free(mallocThenFree);

}

#endif

if ( n == 0 )

return( F0 );

else if ( n == 1 )

return( F1 );

else

return( F(n-1) + F(n-2) );

}

//---------------------------------------------------

void UnusedFunction1(void)

//---------------------------------------------------

{

}

//---------------------------------------------------

void UnusedFunction2()

//---------------------------------------------------

{

}

Sample Program Dialog (with TRACESTACK defined)

n? 5

1) stdout = 00425A78

2) stdin = 00425A58

3) sizeof(FILE) = 20

4) &main() = 0040100A

5) &F() = 00401005

6) &UnusedFunction1 = 0040100F

7) &UnusedFunction2 = 00401014

8) &F1 = 0042301C

9) &calls = 00426794

10) &n = 0012FF7C

11) &i = 0012FF78

12) &Fn = 0012FF74

13) &totalCalls = 0012FF70

14) calls = 00430060

15) &calls[0] = 00430060

16) &calls[n] = 00430074

17) totalCalls = 00430030

18) *totalCalls = 00431FF0

19) **totalCalls = -842150451

20) &"n? " = 00423064

21) &"n? " = 00423064

22) &"%d" = 00423174

n = 5, &n = 0012FF20, memoryLeak = 00431FC0, mallocThenFree = 00431F80

n = 4, &n = 0012FEC0, memoryLeak = 00431F90, mallocThenFree = 00431F50

n = 3, &n = 0012FE60, memoryLeak = 00431F60, mallocThenFree = 00431F20

n = 2, &n = 0012FE00, memoryLeak = 00431F30, mallocThenFree = 00431EF0

n = 1, &n = 0012FDA0, memoryLeak = 00431F00, mallocThenFree = 00431EC0

n = 0, &n = 0012FDA0, memoryLeak = 00431ED0, mallocThenFree = 00431E90

n = 1, &n = 0012FE00, memoryLeak = 00431EA0, mallocThenFree = 00431E60

n = 2, &n = 0012FE60, memoryLeak = 00431E70, mallocThenFree = 00431E30

n = 1, &n = 0012FE00, memoryLeak = 00431E40, mallocThenFree = 00431E00

n = 0, &n = 0012FE00, memoryLeak = 00431E10, mallocThenFree = 00431DD0

n = 3, &n = 0012FEC0, memoryLeak = 00431DE0, mallocThenFree = 00431DA0

n = 2, &n = 0012FE60, memoryLeak = 00431DB0, mallocThenFree = 00431D70

n = 1, &n = 0012FE00, memoryLeak = 00431D80, mallocThenFree = 00431D40

n = 0, &n = 0012FE00, memoryLeak = 00431D50, mallocThenFree = 00431D10

n = 1, &n = 0012FE60, memoryLeak = 00431D20, mallocThenFree = 00431CE0

F( 5) = 5

F[ 0] called 3 times

F[ 1] called 5 times

F[ 2] called 3 times

F[ 3] called 2 times

F[ 4] called 1 times

F[ 5] called 1 times

=============================

Total calls 15 times

23) calls = 00430060

24) calls[n] = -572662307

25) *totalCalls = 00431FF0

26) **totalCalls = -572662307

27) totalCalls = 00430030

28) *totalCalls = DDDDDDDD

Sample Program Dialog (with TRACESTACK not defined)

n? 30

1) stdout = 00425A78

2) stdin = 00425A58

3) sizeof(FILE) = 20

4) &main() = 0040100A

5) &F() = 00401005

6) &UnusedFunction1 = 0040100F

7) &UnusedFunction2 = 00401014

8) &F1 = 0042301C

9) &calls = 00426794

10) &n = 0012FF7C

11) &i = 0012FF78

12) &Fn = 0012FF74

13) &totalCalls = 0012FF70

14) calls = 00431F70

15) &calls[0] = 00431F70

16) &calls[n] = 00431FE8

17) totalCalls = 00430080

18) *totalCalls = 00430050

19) **totalCalls = -842150451

20) &"n? " = 00423444

21) &"n? " = 00423444

22) &"%d" = 00423198

F(30) = 832040

F[ 0] called 514229 times

F[ 1] called 832040 times

F[ 2] called 514229 times

F[ 3] called 317811 times

F[ 4] called 196418 times

F[ 5] called 121393 times

F[ 6] called 75025 times

F[ 7] called 46368 times

F[ 8] called 28657 times

F[ 9] called 17711 times

F[10] called 10946 times

F[11] called 6765 times

F[12] called 4181 times

F[13] called 2584 times

F[14] called 1597 times

F[15] called 987 times

F[16] called 610 times

F[17] called 377 times

F[18] called 233 times

F[19] called 144 times

F[20] called 89 times

F[21] called 55 times

F[22] called 34 times

F[23] called 21 times

F[24] called 13 times

F[25] called 8 times

F[26] called 5 times

F[27] called 3 times

F[28] called 2 times

F[29] called 1 times

F[30] called 1 times

=============================

Total calls 2692537 times

23) calls = 00431F70

24) calls[n] = -572662307

25) *totalCalls = 00430050

26) **totalCalls = -572662307

27) totalCalls = 00430080

28) *totalCalls = DDDDDDDD