m = 10**9+7
n, k, x = map(int, input().split())

last_one, last_other = 1, 0
for i in range(1, n-1):
    last_one, last_other = (k-1) * last_other, (k-2) * last_other + last_one
#    print(last_one, last_other)
r = (k-1) * last_other + last_one - (last_one if x == 1 else last_other)
    
#r = pow(k-1, n-3) # up to previous-to-last layer
#same = r//(k-1) # same number as in last place
#r = (k-1) * same + (k-2) * (r - same)
print(r % m)