// verifast_options{disable_overflow_check target:ILP32}

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

extern void __assert_fail(const char *, const char *, unsigned int, const char *) __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__));
void reach_error() //@ requires false; 
//@ ensures true;
{ __assert_fail("0", "sumt2.c", 3, "reach_error"); }
extern void abort(void);
void assume_abort_if_not(int cond) //@ requires true; 
//@ ensures true;
{
  if(!cond) {abort();}
}
void __VERIFIER_assert(int cond) //@ requires integer(&SIZE, ?veri_req_SIZE) &*& (cond != 0); 
//@ ensures integer(&SIZE, ?veri_ens_SIZE) &*& ((cond != 0) && (veri_req_SIZE == veri_ens_SIZE));
{
  if (!(cond)) {
    ERROR: {reach_error();abort();}
  }
  return;
}
int SIZE = 20000001;
unsigned int __VERIFIER_nondet_uint();//@ requires true; 
//@ ensures true;

int main() //@ requires module(sumt2__verifast_instrumented_modified, true); 
//@ ensures junk();
{
  unsigned int n,i,j,l=0;
//@ invariant integer(&SIZE, ?veri_req_SIZE) &*& true;
  n = __VERIFIER_nondet_uint();
  if (!(n <= SIZE)) return 0;
  i = 0;
  j = 0;
  l=0;
  while( l < n )//@ invariant integer(&SIZE, ?veri_inv_SIZE) &*& (((i + j) % 4294967296) == l);
 {
	
	  if(!(l%2))
	    i = i + 1;
	  else 
		  j = j+1;
    l = l+1;
  }
  __VERIFIER_assert((i+j) == l);
  return 0;
}