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):
    return len(str(n))

def main():
    mode="filee"
    if mode=="file":f=open("test.txt","r")
    get = lambda :[int(x) for x in (f.readline() if mode=="file" else input()).split()]
    [w,m,k]=get()
    ans=0
    while w>= (10**s(m)-m)*s(m)*k:
        w-=(10**s(m)-m)*s(m)*k
        ans+=(10**s(m)-m)
        m=10**s(m)
    w=w//(k*(s(m)))
    ans+=(w)
    print(ans)
    
    if mode=="file":f.close()

if __name__=="__main__":
    main()
