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())
limits=list()

dp=list()
dp.append(0)
lim=10


while(lim<1000000000000000):
    dp.append(lim-1)
    lim*=10

answer=0
index=1
while(dp[index]<n):
    number=dp[index]-dp[index-1]
    answer+=number*len(str(dp[index]))
    index+=1

answer+=(n-dp[index-1])*len(str(dp[index]))

print(answer)
