#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < n; i++)
using ll = long long;
using graph = vector<vector<int>>;

const ll mod = 998244353;
const int INF = 1001001001;

int digit(int n){
    int ret = 0;
    while(n){
        n /= 10;
        ret++;
    }
    return ret;
}

int main(){
    int n; cin >> n;
    int dgt = digit(n);
    int ans = 0;
    for(int i = 2; i <= dgt; i++){
        if(i == 2){
            int tmp = min(n, 99);
            ans += tmp / 3 - 3;
        }
        else{
            if(i == dgt){
                int top = n / pow(10, dgt - 1), res = 1;
                int cal = n;
                if(top % 3 == 0){
                    int cnt = 1;
                    while(cal > 10){
                        cnt *= (cal % 10) / 3 + 1;
                        cal /= 10;
                    }
                    ans += cnt;
                }
                else{
                    ans += (top / 3) * pow(4, dgt - 1);
                }
                
            }
            else{
                ans += pow(4, i - 1) * 3;
            }
        }
    }
    cout << ans << endl;
}