#include<bits/stdc++.h> using namespace std; //int a; //int n,a,b,sum=0; //int n; //double a,b,sum,c; int n,a,sum; int main(){ /**cin>>a; int jsum=0; int osum=0; for(int i=1;i<=a;i++){ if(i%2==0) osum+=i; else jsum+=i; } cout<<jsum<<" "<<osum; /**cin>>n; for(int i=2;i<=n;i++){ if(i%2==0) sum+=i; else sum-=i; } cout<<sum+1; 3.30作业: cin>>n; for(int i=2;i<=(n-1);i++){ if(n%i!=0) { cout<<"No"; return 0; } } cout<<"Yes"; } return 0; /a=100; c=100; b=0; for(int i=1;i<=10;i++){ a/=2; sum=a; } for(int i=1;i<=11;i++){ c/=2; b+=c; } printf("%.6f",b); cout<<endl; printf("%.6f",a); }**/ cin>>n>>a; for(int i=n;i<=a;i++){ if(i%13==0) sum+=i; } cout<<sum; return 0; }