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.
# print(9)

# ans = 0;
# for i in range(10,100):
#     x=list(str(i))
#     ans+=len(x);
# print(ans)

# ans = 0;
# for i in range(100,1000):
#     x=list(str(i))
#     ans+=len(x);
# print(ans)

# ans = 0;
# for i in range(1000,10000):
#     x=list(str(i))
#     ans+=len(x);
# print(ans)
    
# ans = 0;
# for i in range(10000,100000):
#     x=list(str(i))
#     ans+=len(x);
# print(ans)
    
# ans = 0;
# for i in range(100000,1000000):
#     x=list(str(i))
#     ans+=len(x);
# print(ans)
# print()
# print()


n=int(input())
if n<=9:
    print(n)
else:
    R=len(str(n))-1;
    ans = 0;
    V=0;
    while(R!=0):
        A=(R)*9;
        B=10**(R-1);
        ans+=(A*B);
        if V==0:
            V=1;
            N=B*10;
            J=(n-N)+1;
            ans+=(J*len(str(n)))
        R-=1;
    print(ans)
              
            
    
# s = input()
# length = len(s)
# count = (int(s)-10**(length-1)+1)*length
# for i in range(length-1,0,-1):
#     count += 9*(10**(i-1))*i
# print(count)