题解

#include<iostream>
using namespace std;
int aaa(int a){
int x=a,s=0;
while(x!=0){
s+=x%10;
x/=10;

}
return s; 

}
int main(){
int a,b,s=0;
cin>>a>>b;
for(int i=a;i<=b;i++){
s+=aaa(i);
}

cout<<s;
return 0;

}