#include<stdio.h>
#include<algorithm>
#include<iostream>
using namespace std;
long long b,i,x,v,c,ans,anc;
int j,k,a[20];
main(){
// freopen("a.in","r",stdin);
// freopen("a.out","w",stdout);
cin>>b;
k=0; x=1; j=0;
while(b!=0) {a[k]=b%10; b/=10; k++;} for (i=1; i<k; i++) x*=10; if (k==0) x=0; //cout<<x<<" ";
k--;
while(x!=0) {
v=45*(x/10)*k;
c=(a[k]*(a[k]-1)/2)*x+v*a[k]+a[k];
ans+=j*a[k]*x+c; j+=a[k];
x/=10; k--;
} //cout<<ans<<" ";
ans-=j;
cin>>b;
k=0; x=1; j=0;
while(b!=0) {a[k]=b%10; b/=10; k++;} for (i=1; i<k; i++) x*=10; //cout<<x;
k--;
while(x!=0) {
v=45*(x/10)*k; //cout<<"v=="<<v<<" ";
c=(a[k]*(a[k]-1)/2)*x+v*a[k]+a[k]; //cout<<"c=="<<c<<" ";
anc+=j*a[k]*x+c; j+=a[k]; //cout<<"anc=="<<anc<<" ";
x/=10; k--; //cout<<endl;
}
cout<<anc-ans;
}
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