main()1 main() 2 { 3 char c; 4 char d; 5 int nbits; 6 c = -1; 7 for (nbits = 1 ; nbits < 100; nbits++) { 8 d = (1 << nbits) - 1; 9 if (d == c) 10 break; 11 } 12 if (nbits == 100) 13 abort(); 14 exit(0); 15 } 16