added weekly exercises of isp-ws25

c/isp-ws25/weeklies/week07/w07ex01.c

@@ -0,0 +1,89 @@
+/*
+In this task, you should get familiar with malloc() and free().
+In addition, you should implement the functions
+- fillArray(int size, int base_number)
+- printArray(int* numbers, int size).
+
+main:
+- user can enter the size of the integer array
+- user can enter the base number that is used to fill the array
+- print "Memory allocation failed\n" if memory allocation in fillArray failed
+- immediately return exit code 1
+- free the allocated memory using free() at the end.
+
+call createAndFillArray(int size, int base_number)
+- create array by allocating enough memory for it on the heap using malloc()
+- if memory allocation is not successful, return NULL
+- After allocating fill the array with integer values
+  with multiples of base_number using pointer arithmetic
+- Return pointer to array at the end of the function
+
+call printArray(int* numbers, int size)
+- print the array using pointer arithmetic
+
+Examples:
+
+Size: 5
+Fill numbers array with multiples of: 3
+3 6 9 12 15
+
+Size: 4
+Fill numbers array with multiples of: 5
+5 10 15 20
+
+Size: 12
+Fill numbers array with multiples of: 100
+100 200 300 400 500 600 700 800 900 1000 1100 1200
+*/
+
+#include <stdio.h>
+#include <stdlib.h> // TODO: Include the required header file
+
+int* createAndFillArray(int size, int base_number)
+{
+  // TODO: Allocate memory
+  int *numbers = (int*) malloc( size * sizeof(int) );
+  // TODO: Check if memory could be allocated
+  if ( numbers == NULL ) return NULL;
+
+  // TODO: Fill the array with multiples of base_number using pointer arithmetic and return it
+  for ( int position = 0 ; position < size; position++ )
+  {
+    *(numbers + position) = base_number * ( position + 1 );
+  }
+
+  return numbers;
+}
+
+void printArray(int* numbers, int size)
+{
+  for (int position = 0; position < size; position++)
+  {
+    printf("%d ", *(numbers + position));
+  }
+  // TODO: Print the array using pointer arithmetic
+}
+
+int main(void)
+{
+  int size = 0;
+  printf("Size: ");
+  scanf("%d", &size);
+  
+  int base_number = 0;
+  printf("Fill numbers array with multiples of: ");
+  scanf("%d", &base_number);
+
+  int* numbers = createAndFillArray(size, base_number);
+  if ( numbers == NULL )
+  {
+    printf("Memory allocation failed\n");
+    return 1; // TODO: Return 1 if the memory allocation was not successful
+  }
+
+  printArray(numbers, size);
+
+  free(numbers); // TODO: Free the allocated memory
+
+  return 0;
+}