#include <iostream> #include<string> #include<set> #include<map> #include<vector> #define ll long long int using namespace std; ll pow(ll b, ll e){ if(e==0) return 1; if(e==1) return b; ll x = pow(b, e >> 1); if(e%2==0) return (x*x); else return (((x*x))*b); } int main() { long long int a, b; cin>>a>>b; long long int sol=0; if(a>9) sol=0; else{ if(b<=10){ sol=b-a; cout<<sol; return 0; } ll bb=10-a; ll v10=10; ll p10=1; while(v10<=b){ sol+=pow(bb, p10); v10*=10; p10++; } vector<int> st; ll baux=b; while(baux>0){ st.push_back(baux%10); baux/=10; } bool ok=true; for(int i=st.size()-1;ok&& i>=0; i--){ if(st[i]<a){ ok=false; } else{ ll c=st[i]-a; sol+=(c* pow(bb, i)); } } } cout<<sol; return 0; }