#include <bits/stdc++.h>
using namespace std;
int shuzi(int i)
{
    do{
        if(i%10==7) return 1;
    }while(i/=10);
    return 0;
}
int main()
{
    int m;
    set<int> s;
    while(cin>>m)
    {
        s.clear();
        for(int i=1;i<=m;++i)
            if(shuzi(i)||i%7==0)
                s.insert(i);
        cout<<s.size()<<endl;
    }
}