# include<iostream> using namespace std; int main(){ int a,b,c=0,d=0; cin>>a>>b; d=b-(a-1); for(int i=a;i<=b;i++){ c=i; while(c!=0){ if(c%10==4||c%100==62){ d--; break; } c=c/10; } } cout<<d; return 0; }