1extern void abort (void);
2extern void exit (int);
3
4main()
5{
6    int a,b,c;
7    int *pa, *pb, *pc;
8    int **ppa, **ppb, **ppc;
9    int i,j,k,x,y,z;
10
11    a = 10;
12    b = 20;
13    c = 30;
14    pa = &a; pb = &b; pc = &c;
15    ppa = &pa; ppb = &pb; ppc = &pc;
16    x = 0; y = 0; z = 0;
17
18    for(i=0;i<10;i++){
19        if( pa == &a ) pa = &b;
20        else pa = &a;
21        while( (*pa)-- ){
22            x++;
23            if( (*pa) < 3 ) break;
24            else pa = &b;
25        }
26        x++;
27        pa = &b;
28    }
29
30    if ((*pa) != -5 || (*pb) != -5 || x != 43)
31      abort ();
32
33    exit (0);
34}
35