// verifast_options{disable_overflow_check target:ILP32}

extern void abort(void);//@ requires true; 
//@ ensures true;


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() //@ requires false; 
//@ ensures true;
{ ((void) sizeof ((0) ? 1 : 0), __extension__ ({ if (0) ; else __assert_fail ("0", "assert.h", 3, __extension__ __PRETTY_FUNCTION__); })); }
extern void abort(void);
void assume_abort_if_not(int cond) //@ requires true; 
//@ ensures true;
{
  if(!cond) {abort();}
}
void __VERIFIER_assert(int cond) //@ requires (cond != 0); 
//@ ensures (cond != 0);
{
  if (!(cond)) {
      ERROR: {reach_error();abort();}
  }
  return;
}
int __VERIFIER_nondet_int();//@ requires true; 
//@ ensures true;

int main() //@ requires module(ddlm2013__verifast_instrumented_modified, true); 
//@ ensures junk();
{
    unsigned int i,j,a,b;
    int flag = __VERIFIER_nondet_int();
    a = 0;
    b = 0;
    j = 1;
    if (flag) {
        i = 0;
    } else {
        i = 1;
    }
    while (__VERIFIER_nondet_int())//@ invariant ((flag == 0) || (((0 == (i % 2)) && (a == b)) && (((a + 1) % 4294967296) == (((b + j) + (i * 4294967295)) % 4294967296))));
 {
        a++;
        b += (j - i);
        i += 2;
        if (i%2 == 0) {
            j += 2;
        } else {
            j++;
        }
    }
    if (flag) {
        __VERIFIER_assert(a == b);
    }
    return 0;
}