A388.整数各位之和

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