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", "sum03-2.c", 3, __extension__ __PRETTY_FUNCTION__); })); }
void __VERIFIER_assert(int cond) {
  if (!(cond)) {
    ERROR: {reach_error();abort();}
  }
  return;
}
unsigned int __VERIFIER_nondet_uint();
int main() {
  unsigned int sn=0;
  unsigned int loop1=__VERIFIER_nondet_uint(), n1=__VERIFIER_nondet_uint();
  unsigned int x=0;
  while(1) {
    sn = sn + (2);
    x++;
    __VERIFIER_assert(sn==x*(2) || sn == 0);
  }
}