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