#include <cstdio>
#include <ctime>

int T;
int M, K;

int main() {
  freopen("Sequence.in", "r", stdin);
  freopen("Sequence.out", "w", stdout);
  scanf("%d", &T);
  while (T--) {
    bool ok = false;
    scanf("%d %d", &M, &K);
    for (int x = 0; x <= M; ++x) {
      if (clock() > 1900) break;
      int y = M - x;
      if ((__builtin_popcount(x) ^ __builtin_popcount(y)) == K) {
        ok = true;
        printf("2\n%d %d\n", x, y);
        break;
      }
    }
    if (!ok) {
      printf("-1\n");
    }
  }
  return 0;
}