#include<bits/stdc++.h> using namespace std; bool is_leap(int year){ if(year%4==0&&year%100!=0||year%400==0){ return true; } return false; } int main(){ int x,y,cnt=0; cin >> x >> y; for(int i=x;i<=y;i++){ if(is_leap(i)) cnt++; } cout << cnt; return 0; }