Function which is returning pointer to pointer in c

int** ibm()

{

    static int a[]={4,8,12,16};

    static int *pointer=a;

    static int **p=&pointer;

    return p;

}

void main(){

    int **ptr;

    ptr=ibm();

    clrscr();

    printf("%d",++**ptr);

    getch();

}

Output:5