R=range
I=input
Q=10**9+7
def C(A,B):return[A[0]*B[0],A[1]*B[0]+A[0]*B[1],A[2]*B[0]+2*A[1]*B[1]+A[0]*B[2]]
def P(M,N):
	a=[[[0]*3,[0]*3]for i in R(2)]
	for i in R(2):
		for j in R(2):
			for k in R(2):
				t=C(M[i][k],N[1^k][j])
				for m in R(3):a[i][j][m]+=t[m]
			for m in R(3):a[i][j][m]%=Q
	return a
t=[[[0]*3,[1,0,0]],[[1,0,0],[0]*3]]
for c in I():t=P(t,[[[c<'1']*3,[1,0,0]],[[1,0,0],[c>'0']*3]])
p=[[v[:]for v in m]for m in t]
K=int(I())-1
while K:
	if K&1:t=P(t,p)
	p=P(p,p);K>>=1
print(sum(sum(v[2]for v in m)for m in t)%Q)