// what is matter? never mind. 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,sse4,popcnt,abm,mmx,avx,avx2") 
#include<bits/stdc++.h>
#define For(i,a,b) for(int i=(a);i<=(b);++i)
#define Rep(i,a,b) for(int i=(a);i>=(b);--i)
#define ll long long
//#define int long long
#define ull unsigned long long
#define SZ(x) ((int)((x).size()))
#define ALL(x) (x).begin(),(x).end()
using namespace std;
inline int read()
{
    char c=getchar();int x=0;bool f=0;
    for(;!isdigit(c);c=getchar())f^=!(c^45);
    for(;isdigit(c);c=getchar())x=(x<<1)+(x<<3)+(c^48);
    if(f)x=-x;return x;
}

#define fi first
#define se second
#define pb push_back
#define mkp make_pair
typedef pair<int,int>pii;
typedef vector<int>vi;

#define maxn 2000005
#define inf 0x3f3f3f3f

int n,m;
char s[maxn];

int len[maxn],fa[maxn],ch[maxn][26],sz[maxn];
int pos[maxn],edp[maxn],anc[maxn][21];
int tot=1,lst=1;
vi e[maxn];
void append(int c,int id)
{
	int u=++tot,p=lst;
	pos[id]=u,edp[u]=id;
	sz[u]=1,len[u]=len[p]+1;
	for(;p&&!ch[p][c];p=fa[p])ch[p][c]=u;
	if(!p)fa[u]=1;
	else{
		int q=ch[p][c];
		if(len[q]==len[p]+1)fa[u]=q;
		else{
			int nq=++tot;
			len[nq]=len[p]+1; fa[nq]=fa[q]; edp[nq]=edp[q];
			memcpy(ch[nq],ch[q],sizeof ch[q]);
			for(;p&&ch[p][c]==q;p=fa[p])ch[p][c]=nq;
			fa[u]=fa[q]=nq;
		}
	}lst=u;
}
int c[maxn],b[maxn];
void radixsort(){
	memset(c,0,sizeof c);
	For(i,2,tot)e[fa[i]].pb(i);
	For(i,1,tot)++c[len[i]];
	For(i,1,tot)c[i]+=c[i-1];
	For(i,1,tot)b[c[len[i]]--]=i;
	Rep(i,tot,2)sz[fa[b[i]]]+=sz[b[i]];
	For(i,1,tot){
		int u=b[i];
		anc[u][0]=fa[u];
		For(j,1,20)anc[u][j]=anc[anc[u][j-1]][j-1];
	}
}
int jump(int u,int l){
	Rep(i,20,0)if(anc[u][i]&&len[anc[u][i]]>=l)u=anc[u][i];
	return u;
}

int dfn[maxn],idx,out[maxn];
void dfs(int u){
	dfn[u]=++idx;
	for(int v:e[u])dfs(v);
	out[u]=idx;
}

struct bit{
	vector<int>tr;
	int n;
	void init(int N){n=N,tr=vector<int>(N+1,0);}
	void add(int x,int y){for(;x<=n;x+=x&-x)tr[x]+=y;}
	int ask(int x){
		int s=0;
		for(;x;x^=x&-x)s+=tr[x];
		return s;
	}
	void down(){For(i,1,n)tr[i]+=tr[i^(i&-i)];}
}tr;

int occ(int l,int r){
	int u=jump(pos[r],r-l+1);
	return tr.ask(out[u])-tr.ask(dfn[u]-1);
}

ll f[maxn];
int st[maxn],tp;

signed main()
{
	scanf("%s",s+1),n=strlen(s+1);
	reverse(s+1,s+n+1);
	For(i,1,n) append(s[i]-'a',i);
	radixsort(),dfs(1);
	tr.init(tot);
	For(i,1,n){
		tr.add(dfn[pos[i]],1);
//		For(j,1,i)cout<<occ(j,i)<<" "; cout<<"\n";
		f[i]=1;
		For(j,1,i-1) f[i]=max(f[i],occ(j+1,i)-f[j]);
//		while(tp){
//			int j=st[tp];
//			f[i]=max(f[i],occ(j+1,i)-f[j]);
//			if(f[i]<=f[j])--tp;
//			else break;
//		}
//		st[++tp]=i;
	}
	cout<<f[n];
	return 0;
}
/*
1 2 3
*/