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.
from sys import stdin; inp = stdin.readline
from math import dist, ceil, floor, sqrt, log
def IA(): return list(map(int, inp().split()))
def FA(): return list(map(float, inp().split()))
def SA(): return inp().split()
def I(): return int(inp())
def F(): return float(inp())
def S(): return inp()

def main():
    n = I()
    dig = len(str(n))
    if dig < 2:
        return n 
    else:
        count = 9
        for i in range(1, dig):
            res = '1' + '0'*i
            res = int(res)
            cap = '9' + '9'*i
            cap = int(cap)
            if i < dig-1:
                count += (cap-res+1)*(i+1)
            else:
                count += (n-res+1)*(i+1)
        return count

if __name__ == '__main__':
    print(main())