Pointer Mastery

Your Task

Create a collection of C programs that implement a complete pointer toolkit. Each program must compile without warnings using gcc -Wall -Wextra, run without memory leaks, and demonstrate the specific pointer concepts listed in the requirements.

Your toolkit must include ALL of the following programs. Each program is mandatory and will be tested individually.

// Example function signatures
void demonstrate_basic_pointers(void);
void demonstrate_pointer_to_pointer(void);
void print_variable_info(const char *name, void *ptr, size_t size);

// Must use pointer parameters to modify caller's variables
void swap_int(int *a, int *b) {
    int temp = *a;
    *a = *b;
    *b = temp;
}

// Example function signatures
int* create_array(int size);
void fill_array(int *arr, int size);
int calculate_sum(int *arr, int size);
double calculate_average(int *arr, int size);
int* resize_array(int *arr, int old_size, int new_size);
void reverse_array(int *arr, int size);
void free_array(int *arr);

// Must use pointer arithmetic, NOT array indexing
int my_strlen(const char *str) {
    const char *p = str;
    while (*p != '\0') {
        p++;
    }
    return p - str;
}

// Must allocate row pointers, then each row
int** create_matrix(int rows, int cols) {
    int **mat = (int **)malloc(rows * sizeof(int *));
    if (mat == NULL) return NULL;
    
    for (int i = 0; i < rows; i++) {
        mat[i] = (int *)malloc(cols * sizeof(int));
        if (mat[i] == NULL) {
            // Free previously allocated rows
            for (int j = 0; j < i; j++) free(mat[j]);
            free(mat);
            return NULL;
        }
    }
    return mat;
}

typedef double (*Operation)(double, double);

double add(double a, double b) { return a + b; }
double subtract(double a, double b) { return a - b; }
// ... more operations

int main() {
    Operation operations[] = {add, subtract, multiply, divide, power};
    const char *names[] = {"+", "-", "*", "/", "^"};
    // Menu-driven calculator using operations array
}

typedef struct {
    char name[50];
    int age;
    float gpa;
} Student;

int compare_by_name(const void *a, const void *b);
int compare_by_age(const void *a, const void *b);
int compare_by_gpa_desc(const void *a, const void *b);

Create a public GitHub repository with the exact name shown below:

Required Files

pointer-mastery-toolkit/
├── pointer_basics.c       # Program 1: Pointer fundamentals
├── swap.c                 # Program 2: Swap functions
├── dynamic_array.c        # Program 3: Dynamic array operations
├── string_pointers.c      # Program 4: String manipulation
├── matrix_dynamic.c       # Program 5: 2D dynamic matrices
├── calculator.c           # Program 6: Function pointer calculator
├── sorting.c              # Program 7: qsort with comparators
├── Makefile               # Build all programs with: make all
└── README.md              # Documentation (see requirements below)

CC = gcc
CFLAGS = -Wall -Wextra -std=c11

all: pointer_basics swap dynamic_array string_pointers matrix_dynamic calculator sorting

pointer_basics: pointer_basics.c
	$(CC) $(CFLAGS) -o pointer_basics pointer_basics.c

# ... similar rules for other programs

clean:
	rm -f pointer_basics swap dynamic_array string_pointers matrix_dynamic calculator sorting

Your assignment will be graded on the following criteria: