for i in range(int(input())):
    a, b, c = tuple(map(int, input().split()))

    stones=0
    while(c>=2 and b>=1):
        stones+=3
        c-=2
        b-=1
    while(b>=2 and a>=1):
        stones+=3
        b-=2
        a-=1

    print(stones)