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