#include<bits/stdc++.h> using namespace std; int sum(int x,int y){ int sum=0; for(int i=x;i<=y;i++){ if(i%400==0||i%4==0&&i%100!=0){ sum+=1; } } return sum; } int main(){ int a,b,c; cin>>a>>b; c=sum(a,b); cout<<c; }