MOD =10**9+7
A,B,C=map(int,input().split())
K=int(input())
r=1
t=2
while K>0:
    if K%2==1:r=(r*t)%(MOD-1)
    t=(t*t)%(MOD-1)
    K=K//2
ans=1
p=(((A*B)%MOD)*C)%MOD 
while r>0:
    if r%2==1:ans=(ans*p)%MOD
    p=(p*p)%MOD
    r=r//2

print(ans)