t=int(input())
for i in range(t):
    a,b,c=map(int,input().split())
    ans = 0
    k = min(b,c//2)
    c-=2*k
    b-=k
    ans+=3*k
    k = min(a,b//2)
    b-=2*k
    a-=k
    ans+=3*k
    print(ans)