#include<bits/stdc++.h> using namespace std; int main() { int n,m; int sum=0; cin>>n>>m; for(int i=n; i<=m; i++) { int tmp=i; while(tmp>0) { int g=tmp%10; if(g==4) { sum++; break; } tmp=tmp/10; } tmp=i; while(tmp>0){ int sg=tmp%100; if(sg==62){ sum++; break; } tmp=tmp/10; } } cout<<m-n+1-sum; }