void abort() { };
                                                                                                                                                          
                                                                            
                        
void assume_abort_if_not(int cond) {
  if(!cond) {abort();}
}
extern unsigned int __VERIFIER_nondet_uint();

/*@ 
    requires ((\old(cond) != 0)) && (cond != 0);
    ensures ((\old(cond) != 0)) && (1);
@*/
void __VERIFIER_assert(int cond) {
  if (!(cond)) {
    ERROR: {/*@ assert(0); */;abort();}
  }
  return;
}

int main() {
  unsigned int x = 1;
  unsigned int y = __VERIFIER_nondet_uint();

  if (!(y > 0)) return 0;

/*@
loop invariant (((x == 1) && (1 <= y)));
@*/
  while (x < y) {
    if (x < y / x) {
      x *= x;
    } else {
      x++;
    }
  }

  __VERIFIER_assert(x == y);
}