Vanya got an important task — he should enumerate books in the library and label each book with its number. Each of the *n* books should be assigned with a number from 1 to *n*. Naturally, distinct books should be assigned distinct numbers.

Vanya wants to know how many digits he will have to write down as he labels the books.
The first line contains integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">9</sup>) — the number of books in the library.
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     "text": [
      "13\n",
      "17\n"
     ]
    }
   ],
   "source": [
    "n = int(input())\n",
    "if n < 10:\n",
    "    print(n)\n",
    "elif n < 100:\n",
    "    print((n - 9) * 2 + 9)\n",
    "elif n < 1000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    print((n * 3) + (90 * 2) + 9)\n",
    "elif n < 10000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    print((n * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "elif n < 100000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    print((n * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "elif n < 1000000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    n -= 90000\n",
    "    print((n * 6) + (90000 * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "elif n < 10000000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    n -= 90000\n",
    "    n -= 900000\n",
    "    print((n * 7) + (900000 * 6) + (90000 * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "elif n < 100000000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    n -= 90000\n",
    "    n -= 900000\n",
    "    n -= 9000000\n",
    "    print((n * 8) + (9000000 * 7) + (900000 * 6) + (90000 * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "elif n < 1000000000:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    n -= 90000\n",
    "    n -= 900000\n",
    "    n -= 9000000\n",
    "    n -= 90000000\n",
    "    print((n * 9) + (90000000 * 8) + (9000000 * 7) + (900000 * 6) + (90000 * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)\n",
    "else:\n",
    "    n -= 9\n",
    "    n -= 90\n",
    "    n -= 900\n",
    "    n -= 9000\n",
    "    n -= 90000\n",
    "    n -= 900000\n",
    "    n -= 9000000\n",
    "    n -= 90000000\n",
    "    n -= 900000000\n",
    "    print((n * 9) + (900000000*9)+ (90000000 * 8) + (9000000 * 7) + (900000 * 6) + (90000 * 5) + (9000 * 4) + (900 * 3) + (90 * 2) + 9)"
   ]
  }
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