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))
    count = 0
    for i in range(dig):
        p = pow(10, i)
        if i < dig-1:
            count += (p*9)*(i+1)
        else:
            count += (n-p+1)*(i+1)
    return count

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