CodeForces 373B Making Sequences is Fun

標籤：

Making Sequences is FunTime Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64uSubmit Status Practice CodeForces 373B

Description

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 numbern 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.

Input

The first line contains three integers w (1 ≤ w ≤ 10^{16), m (1 ≤ m ≤ 1016), k (1 ≤ k ≤ 109).}

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 %I64dspecifier.

Output

The first line should contain a single integer — the answer to the problem.

Sample Input

Input

9 1 1

Output

9

Input

77 7 7

Output

7

Input

114 5 14

Output

6

Input

1 1 2

Output

0

 1 #include <stdio.h> 2 #include <string.h> 3 long long SS(long long a) 4 { 5     long long x=0; 6     while(a>0) 7     { 8         a=a/10; 9         x++;10         //printf("%I64d\n",a);11     }12     return x;13 }14 15 long long num(long long x)16 {17     long long i,y=1;18     for(i=1;i<=x;i++)19         y=y*10;20     return y;21 }22 int main()23 {24     long long w,m,k;25     int i,j;26     while(scanf("%I64d %I64d %I64d",&w,&m,&k)!=EOF)27     {28         long long n=0,nu,ww,mm;29         long long oo=SS(m);30         nu=num(oo);31         ww=w/k;32         while(ww>0)33         {34             mm=ww/oo;35             n=n+mm;36             if(n>=nu-m)37             {38                 mm=mm-(n-nu+m);39                 n=nu-m;40                 ww=ww-oo*mm;41                 oo++;42                 nu=num(oo);43             }44             else45             {46                 ww=ww-oo*mm;47             }48             if(mm==0)49                 break;50             //printf("%I64d %I64d %I64d",ww,);51         }52         printf("%I64d\n",n);53     }54     return 0;55 }

View Code

 

CodeForces 373B Making Sequences is Fun