#include<bits/stdc++.h> using namespace std; int main() { int s1 = 0; int s2 = 0; int n, m; cin >> n >> m; for (int i = n; i <= m; i++) { if (i % 13 == 0) { s1 = s1 + i; } else { s2 = s2 + i; } } cout << s1 ; return 0; }