#pragma GCC optimize ("O2")
#pragma GCC target ("avx2")
#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
#define rep(i, n) for(int i = 0; i < (n); i++)
#define rep1(i, n) for(int i = 1; i <= (n); i++)
#define co(x) cout << (x) << "\n"
#define cosp(x) cout << (x) << " "
#define ce(x) cerr << (x) << "\n"
#define cesp(x) cerr << (x) << " "
#define pb push_back
#define mp make_pair
#define chmin(x, y) x = min(x, y)
#define chmax(x, y) x = max(x, y)
#define Would
#define you
#define please


int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);


	string S;
	cin >> S;
	int n = stoi(S);
	int L = S.size();
	int N[20] = {};
	rep(i, L) N[L - i - 1] = S[i] - '0';

	int dp0 = 1, dp1 = 0;

	for (int i = L - 1; i >= 0; i--) {
		dp1 *= 4;
		dp1 += dp0 * ((N[i] + 2) / 3);
		if (N[i] % 3) {
			dp0 = 0;
		}
	}

	rep(i, min(10, n + 1)) {
		if (i % 3 == 0) dp1--;
	}
	for (int i = 10; i <= min(n, 99); i++) {
		int x = i / 10;
		int y = i % 10;
		if (x % 3 != 0 || y % 3 != 0) {
			if ((x + y) % 3 == 0) dp1++;
		}
	}

	co(dp0 + dp1);

	Would you please return 0;
}