local bls, brs = bit.lshift, bit.rshift
local mod = 1000000007
local mfl = math.floor
local function bmul(x, y)
  local x1, y1 = mfl(x / 31623), mfl(y / 31623)
  local x0, y0 = x - x1 * 31623, y - y1 * 31623
  return (x1 * y1 * 14122 + (x1 * y0 + x0 * y1) * 31623 + x0 * y0) % mod
end

local function badd(x, y)
  return (x + y) % mod
end

local function bsub(x, y)
  return x < y and x - y + mod or x - y
end

local function modpow(src, pow)
  local res = 1
  while 0 < pow do
    if pow % 2 == 1 then
      res = bmul(res, src)
      pow = pow - 1
    end
    src = bmul(src, src)
    pow = mfl(pow / 2)
  end
  return res
end

local function modinv(src)
  return modpow(src, mod - 2)
end

local a, b, n = io.read("*n", "*n", "*n")
if n <= 1 then
  print(n)
elseif a == 0 and b == 0 then
  print(0)
elseif b == 0 then
  print(modpow(a, n - 1))
elseif a == 0 then
  if n % 2 == 0 then print(0)
  else
    print(modpow(b, brs((n - 1), 1)))
  end
else
  local z, r = bmul(a, 500000004), 1
  local sq = badd(b, bmul(z, z))

  local resz, resr = 1, 0
  local pow = n
  while 0 < pow do
    if pow % 2 == 1 then
      resz, resr = badd(bmul(resz, z), bmul(sq, bmul(resr, r))), badd(bmul(resz, r), bmul(resr, z))
      pow = pow - 1
    end
    z, r = badd(bmul(z, z), bmul(sq, bmul(r, r))), bmul(badd(z, z), r)
    pow = brs(pow, 1)
  end
  print(resr)
end