def f(x):
	x += 1
	while(x % 10 == 0):
		x //= 10
	return x

a = set()
n = int(input())

while(not(n in a)):
	a.add(n)
	n = f(n)

print(len(a))

#include<bits/stdc++.h>

using namespace std;

int f[10];
string s;

int main()
{
	int n;
	cin >> n;
	cin >> s;
	for(int i = 1; i <= 9; i++)
		cin >> f[i];
	vector<int> diff;
	for(int i = 0; i < n; i++)
		diff.push_back(f[s[i] - '0'] - (s[i] - '0'));
	for(int i = 0; i < n; i++)
		if(diff[i] > 0)
		{
			while(i < n && diff[i] >= 0)
			{
				s[i] = char(f[s[i] - '0'] + '0');
				i++;
			}
			break;
		}
	cout << s << endl;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	int n;
	cin >> n;
	vector<int> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
	}
	
	string res;
	int l = 0, r = n - 1;
	int lst = 0;
	while (l <= r) {
		vector<pair<int, char>> cur;
		if (lst < a[l]) cur.push_back(make_pair(a[l], 'L'));
		if (lst < a[r]) cur.push_back(make_pair(a[r], 'R'));
		sort(cur.begin(), cur.end());
		if (int(cur.size()) == 2) {
			cur.pop_back();
		}
		if (int(cur.size()) == 1) {
			if (cur[0].second == 'L') {
				res += 'L';
				lst = a[l];
				++l;
			} else {
				res += 'R';
				lst = a[r];
				--r;
			}
		} else {
			break;
		}
	}
	
	cout << res.size() << endl << res << endl;
	
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	int n;
	cin >> n;
	vector<int> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
	}
	
	string res;
	int l = 0, r = n - 1;
	int lst = 0;
	while (l <= r) {
		vector<pair<int, char>> cur;
		if (lst < a[l]) cur.push_back(make_pair(a[l], 'L'));
		if (lst < a[r]) cur.push_back(make_pair(a[r], 'R'));
		sort(cur.begin(), cur.end());
		if (int(cur.size()) == 2 && cur[0].first != cur[1].first) {
			cur.pop_back();
		}
		if (int(cur.size()) == 1) {
			if (cur[0].second == 'L') {
				res += 'L';
				lst = a[l];
				++l;
			} else {
				res += 'R';
				lst = a[r];
				--r;
			}
		} else if (int(cur.size()) == 2) {
			int cl = 1, cr = 1;
			while (l + cl <= r && a[l + cl] > a[l + cl - 1]) ++cl;
			while (r - cr >= l && a[r - cr] > a[r - cr + 1]) ++cr;
			if (cl > cr) {
				res += string(cl, 'L');
			} else {
				res += string(cr, 'R');
			}
			break;
		} else {
			break;
		}
	}
	
	cout << res.size() << endl << res << endl;
	
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	int n, k;
	cin >> n >> k;
	if (n < k * 1ll * (k + 1) / 2) {
		cout << "NO" << endl;
		return 0;
	}
	
	int nn = n - k * (k + 1) / 2;
	vector<int> a(k);
	for (int i = 0; i < k; ++i) {
		a[i] = i + 1 + (nn / k) + (i >= k - nn % k);
	}
	
	if (nn != k - 1) {
		cout << "YES" << endl;
		for (int i = 0; i < k; ++i) cout << a[i] << " ";
		cout << endl;
	} else {
		if (k > 3) {
			--a[1];
			++a[k - 1];
		}
		if (k == 2 || k == 3) {
			cout << "NO" << endl;
		} else {
			cout << "YES" << endl;
			for (int i = 0; i < k; ++i) cout << a[i] << " ";
			cout << endl;
		}
	}
	
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	int n;
	cin >> n;
	vector<int> a(n);
	multiset<int> b;
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
	}
	for (int i = 0; i < n; ++i) {
		int x;
		cin >> x;
		b.insert(x);
	}
	
	for (int i = 0; i < n; ++i) {
		auto it = b.lower_bound(n - a[i]);
		if (it == b.end()) it = b.begin();
		cout << (a[i] + *it) % n << " ";
		b.erase(it);
	}
	cout << endl;
	
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	int n;
	cin >> n;
	vector<int> a(n);
	vector<int> cnt(200 * 1000 + 1);
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
		++cnt[a[i]];
	}
	
	sort(a.begin(), a.end());
	a.resize(unique(a.begin(), a.end()) - a.begin());
	
	int l = 0, r = 0;
	int ans = cnt[a[0]];
	for (int i = 0; i < int(a.size()); ++i) {
		int j = i + 1;
		int sum = cnt[a[i]];
		while (a[j] - a[j - 1] == 1 && cnt[a[j]] > 1) {
			sum += cnt[a[j]];
			++j;
		}
		int cr = j - 1;
		if (j < n && a[j] - a[j - 1] == 1) {
			sum += cnt[a[j]];
			cr = j;
		}
		if (ans < sum) {
			ans = sum;
			l = i;
			r = cr;
		}
		i = j - 1;
	}
	
	cout << ans << endl;
	for (int c = 0; c < cnt[a[l]]; ++c) cout << a[l] << " ";
	for (int i = l + 1; i < r; ++i) {
		for (int c = 0; c < cnt[a[i]] - 1; ++c) cout << a[i] << " ";
	}
	for (int c = 0; l != r && c < cnt[a[r]]; ++c) cout << a[r] << " ";
	for (int i = r - 1; i > l; --i) cout << a[i] << " ";
	cout << endl;
	
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int n, m;

void invRow(vector<vector<int>> &a, int idx) {
	for (int pos = 0; pos < m; ++pos) {
		a[idx][pos] ^= 1;
	}
}

void invCol(vector<vector<int>> &a, int idx) {
	for (int pos = 0; pos < n; ++pos) {
		a[pos][idx] ^= 1;
	}
}

int main() {
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
//	freopen("output.txt", "w", stdout);
#endif
	
	cin >> n >> m;
	vector<vector<int>> a(n, vector<int>(m));
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			cin >> a[i][j];
		}
	}
	
	for (int cnt0 = 0; cnt0 <= m; ++cnt0) {
		string r(n, '0');
		string c(m, '0');
		vector<vector<int>> b = a;
		for (int j = 0; j < m; ++j) {
			if ((j < cnt0 && b[0][j] == 1) || (j >= cnt0 && b[0][j] == 0)) {
				invCol(b, j);
				c[j] = '1';
			}
		}
		bool ok = true;
		if (cnt0 < m) {
			for (int i = 1; i < n; ++i) {
				int sum = accumulate(b[i].begin(), b[i].end(), 0);
				if (sum != 0 && sum != m) {
					ok = false;
				} else if (sum == 0) {
					invRow(b, i);
					r[i] = '1';
				}
			}
		} else {
			int idx = -1;
			for (int i = 1; i < n; ++i) {
				int sum = accumulate(b[i].begin(), b[i].end(), 0);
				if (sum != 0 && sum != m) {
					if (idx != -1) ok = false;
					else idx = i;
				}
			}
			if (idx == -1) {
				for (int i = 1; i < n; ++i) {
					int sum = accumulate(b[i].begin(), b[i].end(), 0);
					if (sum == 0) {
						invRow(b, i);
						r[i] = '1';
					}
				}
			} else {
				for (int i = 1; i < idx; ++i) {
					int sum = accumulate(b[i].begin(), b[i].end(), 0);
					if (sum == m) {
						invRow(b, i);
						r[i] = '1';
					}
				}
				if (b[idx][0] == 1) {
					invRow(b, idx);
					r[idx] = '1';
				}
				for (int j = 1; j < m; ++j) {
					if (b[idx][j] < b[idx][j - 1]) {
						ok = false;
					}
				}
				for (int i = idx + 1; i < n; ++i) {
					int sum = accumulate(b[i].begin(), b[i].end(), 0);
					if (sum == 0) {
						invRow(b, i);
						r[i] = '1';
					}
				}
			}
		}
		if (ok) {
			cout << "YES" << endl << r << endl << c << endl;
			return 0;
		}
	}
	
	cout << "NO" << endl;
	
	return 0;
}