We'll define *S*(*n*) for positive integer *n* as follows: the number of the *n*'s digits in the decimal base. For example, *S*(893) = 3, *S*(114514) = 6.

You want to make a consecutive integer sequence starting from number *m* (*m*, *m* + 1, ...). But you need to pay *S*(*n*)·*k* to add the number *n* to the sequence.

You can spend a cost up to *w*, and you want to make the sequence as long as possible. Write a program that tells sequence's maximum length.
The first line contains three integers *w* (1 ≤ *w* ≤ 10<sup class="upper-index">16</sup>), *m* (1 ≤ *m* ≤ 10<sup class="upper-index">16</sup>), *k* (1 ≤ *k* ≤ 10<sup class="upper-index">9</sup>).

Please, do not write the %lld specifier to read or write 64-bit integers in C++. It is preferred to use the cin, cout streams or the %I64d specifier.
def S(n):
    lista = [number for number in str(n)]
    return len(lista)

def diff_to_change(n):
    return 10 ** S(n) - n

line = input()
numbers = line.split(" ")
numbers = [int(x) for x in numbers]

w = numbers[0]
m = numbers[1]
k = numbers[2]


output = 0
while w > 0:
    times_left = (w) // (S(m)*k)
    times_to_change = diff_to_change(m)
    times = min(times_left, times_to_change)
    if times == 0:
        break
    w -= S(m)*k*times
    m += times
    output += times
    
print(output)
	  			 		  	  	 	 	 				 			