In C language. PLEASE be detailed. Why does the first case uses the arrow operator to access digits while the second case uses the . operator to access quizzes. Both are allocated structs with malloc for one of its members. Whats so different that different operators are used? Thank you.

//CASE 1) MAIN

struct integer { int* digits; int size; };

//FUNCTION:

struct nteger* createRandBigInt(intnumDigits) { struct nteger* temp;

temp = (struct *integer) malloc(sizeof(struct integer));

temp->digits = (int *) malloc(numDigits*sizeof(int)); //THIS LINE

temp->size = numDigits; temp->digits[numDigits-1] = 1+ rand()%9; int i; for(i=0; idigits[i] = rand()%10;

return temp; }

//CASE 2) In MAIN:

struct Student {

int student_id;

float *quizzes;

}

//FUNCTION:

struct Student* AllocateStudents( int N, int Q) { struct Students *ptr; int i, j; ptr = (struct Student*) malloc(N *(sizeof(struct Student))); for(i = 0; i < N; ++i) { scanf("%d", &ptr[i].student_id);

ptr[i].quizzes = (float *)malloc(Q * (sizeof(float))); //THIS LINE

for(j = 0; j < *noofquiz; ++j) { scanf("%d", &ptr[i].quizzes[j]); } } return ptr; }