#include<iostream> using namespace std; int main(){ int a,b,sum=0; cin>>a>>b; for(int i=a;i<=b;i++){ int n=i; while(n){ sum+=n%10; n/=10; } } cout<<sum; return 0; }

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