void abort() { };
                                                                                                                                                          
                                                                          
                        
void assume_abort_if_not(int cond) {
  if(!cond) {abort();}
}
/*@ 
    requires (((cond != 0) && (SIZE == 20000001))) && (cond != 0);
    ensures ((((cond != 0) && (\old(SIZE) == SIZE)) && (SIZE == 20000001))) && (1);
@*/
void __VERIFIER_assert(int cond) {
  if (!(cond)) {
    ERROR: {/*@ assert(0); */;abort();}
  }
  return;
}
int SIZE = 20000001;
unsigned int __VERIFIER_nondet_uint();
/*@ 
    requires ((SIZE == 20000001));
    ensures (((\old(SIZE) == SIZE) && (SIZE == 20000001)));
@*/
int main() {
  unsigned int n,i,k;
  n = __VERIFIER_nondet_uint();
  if (!(n <= SIZE)) return 0;
  i = 0;
/*@
loop invariant (((((i == 0) && (n <= 20000001)) || (((((i + 4294967295) % 4294967296) + 1) <= n) && (n <= 20000001))) && (SIZE == 20000001)));
@*/
  while( i < n ) {
    i = i + 1;
  }
  int j = i;
/*@
loop invariant ((((((n <= i) && (SIZE == 20000001)) && (n <= (j % 4294967296))) && ((((((long long) j * 2) + i) % 4294967296) / 3) <= 20000001)) && (((((long long) i * 3) % 4294967296) / 3) <= 20000001)));
@*/
  while( j < n ) {
    j = j+1;
  }
  k = j;
/*@
loop invariant (((((((SIZE == 20000001) && (n <= k)) && ((((((long long) i + k) + j) % 4294967296) / 3) <= 20000001)) && (n <= (j % 4294967296))) && ((((((long long) j * 2) + i) % 4294967296) / 3) <= 20000001)) && (((((long long) i * 3) % 4294967296) / 3) <= 20000001)));
@*/
  while( k < n ) {
    k = k+1;
  }
  __VERIFIER_assert((i+j+k)/3 <= SIZE);
  return 0;
}