// tzl ak IOI! 
 
#include<bits/stdc++.h>
 
#define HEAP priority_queue
#define rep(i, n) for(int i = 0; i < (n); ++i)
#define per(i, n) for(int i = (n) - 1; i >= 0 ; --i)
#define forn(i, l, r) for(int i = (l); i <= (r); ++i)
#define nrof(i, r, l) for(int i = (r); i >= (l); --i)
#define FOR(a, b) for(auto (a): (b))
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define X first
#define Y second
#define eps 1e-6
#define pi 3.1415926535897932384626433832795
#define SZ(x) (int)x.size()
#define ALL(x) x.begin(), x.end()
#define FILL(a, b) memset((a), (b), sizeof((a)))
#define MCPY(a, b) memcpy((a), (b), sizeof((b)))
 
using namespace std;
 
typedef long long LL;
typedef double flt;
typedef vector<int> vi;
typedef vector<LL> vl;
typedef pair<int,int> pii;
typedef pair<int,LL> pil;
typedef pair<LL,int> pli;
typedef pair<LL,LL> pll;
typedef vector<pil> vil;
typedef vector<pii> vii;
typedef vector<pli> vli;
typedef vector<pll> vll;
 
const int iinf = 1e9 + 7;
const LL linf = 1ll << 60;
const flt dinf = 1e60;
 
template <typename T>
inline void scf(T &x)
{
	bool f = 0; x = 0; char c = getchar();
	while((c < '0' || c > '9') && c != '-') c = getchar();
	if(c == '-') { f = 1; c = getchar(); }
	while(c >= '0' && c <= '9') { x = x * 10 + c - '0'; c = getchar(); }
	if(f) x = -x; return;
}
 
template <typename T1, typename T2>
void scf(T1 &x, T2 &y) { scf(x); return scf(y); }
 
template <typename T1, typename T2, typename T3>
void scf(T1 &x, T2 &y, T3 &z) { scf(x); scf(y); return scf(z); }
 
template <typename T1, typename T2, typename T3, typename T4>
void scf(T1 &x, T2 &y, T3 &z, T4 &w) { scf(x); scf(y); scf(z); return scf(w); }
 
inline char mygetchar(){ char c = getchar(); while(c == ' ' || c == '\n') c = getchar(); return c; }
 
template <typename T>
void chkmax(T &x, const T &y){ if(y > x) x = y; return; }
 
template <typename T>
void chkmin(T &x, const T &y){ if(y < x) x = y; return; }
 
#ifdef ONLINE_JUDGE
#define debug(x,c) ;
#else
#define DEBUG
#define debug(x,c) cerr<<#x<<"="<<x<<c;
#endif
 
//---------------------------head----------------------------
 
const int N = 5e5 + 100;
 
struct huge_int
{
	deque<int> num;
	
	void in()
	{
		char c = getchar();
		while(c < '0' || c > '9') c = getchar();
		while(c >= '0' && c <= '9') num.push_front(c - '0'), c = getchar();
		return;
	}
 
	huge_int operator +(const huge_int &a) const
	{
		huge_int b; b.num = num;
		while(SZ(b.num) < SZ(a.num)) b.num.pb(0); b.num.pb(0);
		rep(i, SZ(a.num)) b.num[i] += a.num[i];
		rep(i, SZ(b.num)) if(b.num[i] > 9) b.num[i] -= 10, b.num[i + 1]++;
		if(!b.num.back()) b.num.pop_back();
		return b;
	}
 
	int sum()
	{
		int ret = 0;
		for(auto x: num) ret += x;
		return ret;
	}
 
	void out()
	{
		per(i, SZ(num)) cout<<num[i]; cout<<endl;
	}
}a, b;
 
void TZL()
{
	a.in(); b = a;
	rep(i, 8) a = a + b;
}
 
bool check(int k)
{
	b.num.clear();
	int x = 9 * k;
	while(x) b.num.pb(x % 10), x /= 10;
	b = a + b;
	return b.sum() <= 9 * k;
}
 
void RANK1()
{
	int lb = 0, rb = a.sum();
	while(lb <= rb)
	{
		int mid = lb + rb >> 1;
		if(check(mid)) rb = mid - 1;
		else lb = mid + 1;
	}
	printf("%d\n", lb);
	return;
}
 
#define tzl int
#define ak main
#define IOI ()
tzl ak IOI
{
#undef tzl
#undef ak
#undef IOI
 
	TZL();
	RANK1();
 
#define tzl return
#define caisi 0
#define myy ;
	tzl caisi myy
#undef tzl
#undef caisi
#undef myy
}

Measured memory_bytes: 6408