tj

#include <bits/stdc++.h>
using namespace std;
int main(){
    int a,b,sum = 0;
    cin >> a >> b;
        for(int i = a;i <= b;i++){
            int t = i;
            while(t > 0){
                sum += t % 10;
            t /= 10;
        }
    }
    cout << sum;
}