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>=1 and n<10:
    print(n)
elif n>=10 and n<100:
    print(9+(n-9)*2)
elif n>=100 and n<1000:
    print(9+90*2+(n-99)*3)
elif n>=1000 and n<10000:
    print(9+90*2+900*3+(n-999)*4)
elif n>=10000 and n<100000:
    print(9+90*2+900*3+9000*4+(n-9999)*5)
elif n>=100000 and n<1000000:
    print(9 + 90 * 2 + 900 * 3 + 9000 * 4 +90000*5+ (n - 99999) * 6)
elif n>=1000000 and n<10000000:
    print(9 + 90 * 2 + 900 * 3 + 9000 * 4 +90000*5 +900000*6+ (n - 999999) * 7)
elif n>=10000000 and n<100000000:
    print(9 + 90 * 2 + 900 * 3 + 9000 * 4 + 90000*5 +900000*6+ 9000000*7+ (n - 9999999) * 8)
elif n>=100000000 and n<1000000000:
    print(9 + 90 * 2 + 900 * 3 + 9000 * 4 + 90000*5 +900000*6+ 9000000*7+ 90000000* 8 + (n - 99999999) * 9)
else:
    print(9 + 90 * 2 + 900 * 3 + 9000 * 4 + 90000*5 +900000*6+ 9000000*7+ 90000000* 8 +900000000*9 +10)