#include stdio.h
#include stdlib.h
int main()
{
    int* ptr;
  int n=5, i;
 printf("n is:%d",n);
printf("Entered number of elements: %d\n", n);
 ptr = (int*)malloc(n * sizeof(int));
  if (ptr == NULL) {
 printf("Memory not allocated.\n");
exit(0);
  }
  else {
 printf("Memory successfully allocated using malloc.\n");
  for (i = 0; i  n; ++i){
ptr[i] = i + 1;
  }
printf("The elements of the array are: ");
for (i = 0; i  n; ++i) {
printf("%d, ", ptr[i]);
  }
}
 return 0;
}

Output of the following program