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.
n = int(input())
if(n < 10):
    print(n)
    exit()
if(n < 100):
    print(2 * (n + 1) - 11)
    exit()
if(n < 1000):
    print(3 * (n + 1) - 111)
    exit()
if(n < 10000):
    print(4 * (n + 1) - 1111)
    exit()
if(n < 100000):
    print(5 * (n + 1) - 11111)
    exit()
if(n < 1000000):
    print(6 * (n + 1) - 111111)
    exit()
if(n < 1000000):
    print(7 * (n + 1) - 1111111)
    exit()
if(n < 10000000):
    print(8 * (n + 1) - 11111111)
    exit()
if(n < 100000000):
    print(9 * (n + 1) - 111111111)
    exit()
print(10 * (n + 1) - 111111111)