#想定解法

def member_id(alpha):
    return ord(alpha)-65 # ord("A")=65

def identity_matrix(size):
    return [[0 if i==j else -inf for j in range(size)] for i in range(size)]

def tolopical_matrix_add(A,B):
    C=[[0]*number for _ in range(number)]
    for i in range(number):
        a=A[i]; b=B[i]; c=C[i]
        for j in range(number):
            c[j]=max(a[j],b[j])
    return C

def tolopical_matrix_mul(A,B):
    C=identity_matrix(number)
    for i in range(number):
        ci=C[i]; ai=A[i]
        for k in range(number):
            aik=ai[k]; bk=B[k]
            for j in range(number):
                ci[j]=max(ci[j],aik+bk[j])
    return C

def tolopical_matrix_power(A,k):
    B=identity_matrix(number)
    while True:
        if k&1:
            B=tolopical_matrix_mul(B,A)

        k>>=1
        if k:
            A=tolopical_matrix_mul(A,A)
        else:
            break
    return B

#==================================================
import sys
input=sys.stdin.readline

#==================================================
# #入力部
C=list(map(int,input().split()))
K=list(map(int,input().split()))

inf=float("inf"); number=16; member=26
M=[identity_matrix(number) for _ in range(member)]
N=int(input())

for _ in range(N):
    S,A,B,E=input().split()
    A=int(A)-1; B=int(B)-1; E=int(E)

    for s in S:
        M[member_id(s)][A][B]=M[member_id(s)][B][A]=max(M[member_id(s)][A][B],E)

#==================================================
#トロピカル代数上での累乗を求める.
T=[tolopical_matrix_power(M[alpha],K[alpha])[C[alpha]-1] for alpha in range(member)]

#==================================================
#最終解答

V=[0]*number
for t in T:
    for i in range(number):
        V[i]+=t[i]

ans=max(V)
print(ans if ans>-inf else "Impossible")