#include<iostream> #include<cstring> using namespace std; int main(){ int n,m; cin>>n>>m; int sum=0; for(int i=n;i<=m;i++){ int r=i; while(r!=0){ if(r%10==4){ continue; }else{ if(r%10==2 && r/10%10==6){ continue; }else{ r=r/10; if(r==0){ sum++; } } } } } cout<<sum; return 0; }