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