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