各位！ac啊！关注我！

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