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