#include <iostream> using namespace std; bool isrunnian(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(isrunnian(i)){ sum++; } } cout<<sum; return 0; }