def hs(n,r):
    if n == 1:
        return r;
    else:
        return hs(n-1,r) * 10 + r;
    

n = int(input())
s = 0
for i in range(1,n + 1):
    s +=  hs(i,n)
print(s)

/**************************************************************
	Problem: 1245
	User: admin
	Language: Python
	Result: Accepted
	Time:101 ms
	Memory:34244 kb
****************************************************************/