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Homework #10 Structures (Ch 17), Input & Output (Ch 18), Recursion (Ch 19), Debugging (Ch 20) In order to automate the grading process, please follow the exact instructions for each questions and don’t use extra or unnecessary words (3 points) Consider the code segment below If the variable c’s value is 0x053E, what are the values of variables i, f, and d? union { char c; int i; float f; double d; } x; char* c = &x.c; int* i = &x.i; float* f = &x.f; double* d = &x.d; Answer: i : f: d: (2 points) Explain the bug in the program below struct node { int count; struct node *next; }; int main() { int data = 0; struct node *getdata; getdata->count = data + 1; printf("%d", getdata->count); } Answer: (2 points) Given the C program on the right, what is the missing MSP430 assembly instruction generated by the compiler for the line: struct node { getdata.next = &getdata; Hint: Think about activation records and where each variable is stored in memory Main : 0x8020: 8221 0x8020: 4381 0000 0x8024: 0x8028: 5221 0x802A: 4130 SUB.W CLR.W missing ADD.W RET #4,SP 0x0000(SP) instruction #4,SP Answer: BYU, ECEn/CS 124 Homework #10 int count; struct node *next; }; int main(void) { struct node getdata; getdata.count = 0; getdata.next = &getdata; return 0; } (2 points) The C program below is compiled on a machine in which char’s are byte, int’s and pointers are bytes, and float‘s are bytes a What is the size (in bytes) of the activation record for the function is_it_noble (include the return address)? Answer: b Assuming that periodic_table, x, and y are the only local variables, what is the size (in bytes) of the activation record for the function main? Answer: struct element { char name[10]; int atomic_number; float atomic_mass; }; int is_it_noble(struct element t[], int i) { if ((t[i].atomic_number==2) || (t[i].atomic_number==10) || (t[i].atomic_number==18) || (t[i].atomic_number==36) || (t[i].atomic_number==54) || (t[i].atomic_number==86)) return 1; return 0; } int main(void) { int x, y = 4; struct element periodic_table[10]; x = is_it_noble(periodic_table, y); return x; } (3 points) The following lines of C code appear in a program What will be the output of each printf statement? #define LETTER '1' #define ZERO #define NUMBER 123 printf("%c", 'a'); printf("0x%x", 12288); printf("$%d.%c%d\n", NUMBER, LETTER, ZERO); Answer: BYU, ECEn/CS 124 Homework #10 (3 points) What is the correct statement that uses one scanf function to read two integers into the two variables temp1 and temp2? int temp1; int temp2[1]; Answer: (12 points) What the following print statements print? print statement 10 11 12 output printf("%c %c \n", 'a', 65); Printf("%d %ld\n", 2010, 650000L); Printf("%10d\n", 2010); Printf("%010d\n", 2010); Printf("%o %x\n", 100, 100); printf("%#o %#x\n", 100, 100); printf("%4.2f\n", 3.1416); printf("%+.0e\n", 3.1416); printf("%E\n", 3.1416); printf("%*d\n", 5, 10); printf("%s\n", "A string"); printf("%.*s\n", 5, "A string"); (3 points) Consider the C program below State the complete output if the input is: 27 -1 Answer 1: Answer 2: Answer 3: #include int Power(int a, int b); int main(void) { int x, y, z; printf("\nInput two numbers:"); scanf("%d %d", &x, &y); if (x > && y > 0) z = Power(x, y); else z = 0; printf ("\nResult = %d.", z); } int Power(int a, int b) { if(a < b) return 0; else return (1 + Power(a / b, b)); } BYU, ECEn/CS 124 Homework #10