extern void abort(void);

extern void __assert_fail (const char *__assertion, const char *__file,
      unsigned int __line, const char *__function)
     __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__));
extern void __assert_perror_fail (int __errnum, const char *__file,
      unsigned int __line, const char *__function)
     __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__));
extern void __assert (const char *__assertion, const char *__file, int __line)
     __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__));

void reach_error() { ((void) sizeof ((0) ? 1 : 0), __extension__ ({ if (0) ; else __assert_fail ("0", "sum01_bug02_sum01_bug02_base.case.c", 3, __extension__ __PRETTY_FUNCTION__); })); }

void __VERIFIER_assert(int cond) {
  if (!(cond)) {
    ERROR: {reach_error();abort();}
  }
  return;
}

extern unsigned int __VERIFIER_nondet_uint();
int main() {
  int i, n=__VERIFIER_nondet_uint(), sn=0;
  for(i=1; i<=n; i++) {
    sn = sn + (2);
    if (i==4) sn=-10;
  }
  __VERIFIER_assert(sn==n*(2) || sn == 0);
}