/* Printing consecutive cubes, by Cohen http://www.cs.upc.edu/~erodri/webpage/polynomial_invariants/cohencu.htm */ extern void abort(void); extern void __assert_fail(const char *, const char *, unsigned int, const char *) __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__)); void reach_error() { __assert_fail("0", "cohencu-ll.c", 8, "reach_error"); } extern unsigned short __VERIFIER_nondet_ushort(void); extern void abort(void); void assume_abort_if_not(int cond) { if(!cond) {abort();} } void __VERIFIER_assert(int cond) { if (!(cond)) { ERROR: {reach_error();} } return; } int main() { short a; long long n, x, y, z; a = __VERIFIER_nondet_ushort(); n = 0; x = 0; y = 1; z = 6; while (1) { __VERIFIER_assert(z == 6 * n + 6); __VERIFIER_assert(y == 3 * n * n + 3 * n + 1); __VERIFIER_assert(x == n * n * n); __VERIFIER_assert(y*z - 18*x - 12*y + 2*z - 6 == 0); __VERIFIER_assert((z*z) - 12*y - 6*z + 12 == 0); if (!(n <= a)) break; n = n + 1; x = x + y; y = y + z; z = z + 6; } __VERIFIER_assert(z == 6*n + 6); __VERIFIER_assert(6*a*x - x*z + 12*x == 0); __VERIFIER_assert(a*z - 6*a - 2*y + 2*z - 10 == 0); __VERIFIER_assert(2*y*y - 3*x*z - 18*x - 10*y + 3*z - 10 == 0); __VERIFIER_assert(z*z - 12*y - 6*z + 12 == 0); __VERIFIER_assert(y*z - 18*x - 12*y + 2*z - 6 == 0); return 0; }