int __unbuffered_cnt=0;
int __unbuffered_p0_r1=0;
int __unbuffered_p0_r3=0;
int __unbuffered_p1_r1=0;
int __unbuffered_p1_r3=0;
int __unbuffered_p2_r1=0;
int __unbuffered_p2_r3=0;
int __unbuffered_p3_r1=0;
int __unbuffered_p3_r3=0;
int a=0;
int x=0;
int y=0;
int z=0;

void * P0(void * arg) {
  __unbuffered_p0_r1 = a;
  __unbuffered_p0_r3 = 1;
  x = __unbuffered_p0_r3;
  // Instrumentation for CPROVER
  __unbuffered_cnt++;
}

void * P1(void * arg) {
  __unbuffered_p1_r1 = 2;
  x = __unbuffered_p1_r1;
  __unbuffered_p1_r3 = 1;
  y = __unbuffered_p1_r3;
  // Instrumentation for CPROVER
  __unbuffered_cnt++;
}

void * P2(void * arg) {
  __unbuffered_p2_r1 = y;
  __unbuffered_p2_r3 = 1;
  z = __unbuffered_p2_r3;
  // Instrumentation for CPROVER
  __unbuffered_cnt++;
}

void * P3(void * arg) {
  __unbuffered_p3_r1 = 2;
  z = __unbuffered_p3_r1;
  __unbuffered_p3_r3 = 1;
  a = __unbuffered_p3_r3;
  // Instrumentation for CPROVER
  __unbuffered_cnt++;
}

int main() {
  __CPROVER_ASYNC_0: P0(0);
  __CPROVER_ASYNC_1: P1(0);
  __CPROVER_ASYNC_2: P2(0);
  __CPROVER_ASYNC_3: P3(0);
  __CPROVER_assume(__unbuffered_cnt==4);
  __CPROVER_assert(!(x==2 && z==2 && __unbuffered_p0_r1==1 && __unbuffered_p2_r1==1), "Program proven to be relaxed for PPC, model checker says YES.");
  return 0;
}