xorfire

def go(n, a, d, r, mod):
    mod *= (1 - r) * (1 - r)
    ret = (1 - r % mod) * ((a % mod - (a % mod + n % mod * d % mod) % mod * pow(r % mod, n + 1, mod) % mod) % mod) % mod
    ret += d % mod * r % mod * (1 - pow(r, n, mod)) % mod;
    if (ret > mod): ret -= mod
    ret //= ((1 - r) * (1 - r))
    mod //= (1 - r) * (1 - r)
    if (ret >= mod): print("NOOOO")
    return ret

print(go(10**9+69 , 105253, 330787, 179948, 10**9 + 7))
print(go(10 ** 18, 705000020383, 100000023986, 3746166374021812690, 2717401869))