/* -*- coding: utf-8 -*-
 *
 * 3534.cc:  No.3534 Make Many Fences - yukicoder
 */

#include<cstdio>
#include<algorithm>

using namespace std;

/* subroutines */

int fence(int &n, int &m) {
  int c = min(n / 4, m / 2);
  n -= 4 * c, m -= 2 * c;
  return c * 3;
}

/* main */

int main() {
  int tn;
  scanf("%d", &tn);

  while (tn--) {
    int n, m;
    scanf("%d%d", &n, &m);

    int f = fence(n, m);
    if (n >= 10) {
      int d = (n / 10) * 2;
      n -= d, m += d * 2;
      f += fence(n, m);
    }
    if (n >= 6) {
      n -= 2, m += 4;
      f += fence(n, m);
    }

    printf("%d\n", f);
  }

  return 0;
}