void abort() { }; void assume_abort_if_not(int cond) { if(!cond) {abort();} } /*@ requires ((1 <= cond)) && (cond != 0); ensures ((1 <= cond)) && (1); @*/ void __VERIFIER_assert(int cond) { if (!(cond)) { ERROR: {/*@ assert(0); */;abort();} } return; } int __VERIFIER_nondet_int(); int main() { int lo, mid, hi; lo = 0; mid = __VERIFIER_nondet_int(); if (!(mid > 0 && mid <= 1000000)) return 0; hi = 2*mid; /*@ loop invariant ((((lo + ((long long) mid * 2)) == hi) && (lo <= hi))); @*/ while (mid > 0) { lo = lo + 1; hi = hi - 1; mid = mid - 1; } __VERIFIER_assert(lo == hi); return 0; }