http://codeforces.com/gym/101193/problem/A

#include
     
      using namespace std;#define ll long longconst ll mod=1e9+7;int n[55];int m[55];ll dp[55];ll dfs(int pos,bool lead,bool limit) {    if(pos==-1) {        return 1;    }    if(!limit && !lead && dp[pos]!=-1)        return dp[pos];    int up=limit?n[pos]:9;    int down=m[pos];    ll ans=0;    for(int i=down; i<=up; i++) {        //cout<<"pos="<
      
       <<" i="<
       <
        
         ln)        return 0;    int pos=0;    for(int i=0;i
         
          =0)            m[i]=mm[lm-1-i]-'0';        else            m[i]=0;        //cout<<"n["<
          <<"]="<
           
            <
           
         
        
      
     

 

 

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