mod = 10**9+7

n, k, x = map(int,input().split())
def f():
    m = n-2
    low = 1
    high = 0
    
    for i in range(m):
        low,high = high*(k-1)%mod,low+high*(k-2)%mod
   
    if x == 1:
        return high*(k-1)
    else:
        return high*(k-2) + low
    
print(f()%mod)