#include<bits/stdc++.h>

using namespace std;

#define MAX             100005
#define MOD             1000003
#define eps             1e-6
int fx[] =              {1,-1,0,0};
int fy[] =              {0,0,1,-1};

#define FastRead        ios_base::sync_with_stdio(0);cin.tie(0);
#define fRead           freopen("in.txt","r",stdin);
#define fWrite          freopen ("in.txt","w",stdout);

#define ll              long long
#define ull             unsigned long long
#define ff              first
#define ss              second
#define pb              push_back
#define PI              acos(-1.0)
#define mk              make_pair
#define pii             pair<int,int>
#define pll             pair<LL,LL>
#define vi              vector <int>
#define vl              vector <LL>
#define vp              vector<pii>
#define all(a)          a.begin(),a.end()

#define min3(a,b,c)     min(a,min(b,c))
#define max3(a,b,c)     max(a,max(b,c))
#define min4(a,b,c,d)   min(a,min(b,min(c,d)))
#define max4(a,b,c,d)   max(a,max(b,max(c,d)))

#define FOR(i,a,b)      for(int i=a;i<=b;i++)
#define ROF(i,a,b)      for(int i=a;i>=b;i--)
#define REP(i,b)        for(int i=0;i<b;i++)
#define IT(it,x)	for(it=x.begin();it!=x.end;it++)

#define MEM(a,x)        memset(a,x,sizeof(a))
#define ABS(x)          ((x)<0?-(x):(x))
#define SORT(v)         sort(v.begin(),v.end())
#define REV(v)          reverse(v.begin(),v.end())

//#define NUM 1000005bool flag[NUM];vector <int> prime;inline void sieve(){flag[1]=true;for(int i=4; i<NUM; i+=2){flag[i]=true;}for(int i=3; i*i<=NUM; i+=2){if(!flag[i]){for(int j=i*i; j<NUM; j+=2*i){flag[j]=true;}}}prime.pb(2);for(int i=3; i<NUM; i+=2){if(!flag[i]){prime.pb(i);}}return;}

//inline int NOD(ll n){int div=1;for(int i=0; prime[i]*prime[i]<=n; i++){if(n%prime[i]==0){int cnt=0;while(n%prime[i]==0){n/=prime[i];cnt++;}div*=(cnt+1);}}if(n>1){div*=2;}return div;}

//inline ll BigMod(ll B,ll P,ll M){ll R=1;while(P>0){if(P & 1) R=(R*B)%M;P/=2;B=(B*B)%M;}return R%M;}

//inline void build(int L,int R,int pos){if(L==R){tree[pos]=arr[L];return;}int mid=(L+R)/2;build(L,mid,pos*2+1);build(mid+1,R,pos*2+2);tree[pos]=min(tree[pos*2+1],tree[pos*2+2]);return;}

//inline int query(int ql,int qr,int L,int R,int pos){if(ql>R or qr<L) return MAX;else if(ql<=L and qr>=R) return tree[pos];int mid=(L+R)/2;int p=query(ql,qr,L,mid,2*pos+1);int q=query(ql,qr,mid+1,R,2*pos+2);return min(p,q);}

//void updateRange(int b,int e,int L,int R,int pos,ll val){if(lazy[pos]!=0){tree[pos]+=(R-L+1)*lazy[pos];if(L!=R){lazy[2*pos+1]+=lazy[pos];lazy[2*pos+2]+=lazy[pos];}lazy[pos]=0;}if(L>R or L>e or R<b) return;if(L>=b and R<=e){tree[pos]+=(R-L+1)*val;if(L!=R){lazy[2*pos+1]+=val;lazy[2*pos+2]+=val;}return;}int mid=(L+R)/2;updateRange(b,e,L,mid,2*pos+1,val);updateRange(b,e,mid+1,R,2*pos+2,val);tree[pos]=tree[2*pos+1]+tree[2*pos+2];return;}

//ll getSum(int ql,int qr,int L,int R,int pos){if(lazy[pos]!=0){tree[pos]+=(R-L+1)*lazy[pos];if(L!=R){lazy[2*pos+1]+=lazy[pos];lazy[2*pos+2]+=lazy[pos];}lazy[pos]=0;}if(L>R or ql>R or qr<L) return 0;if(L>=ql and qr>=R) return tree[pos];int mid=(L+R)/2;return getSum(ql,qr,L,mid,2*pos+1)+getSum(ql,qr,mid+1,R,2*pos+2);}

//inline void bfs(int s){MEM(vis,0);vis[s]=1;queue<int>Q;Q.push(s);while(!Q.empty()){int x=Q.front();Q.pop();REP(i,V[x].size()){if(!vis[V[x][i]]){vis[V[x][i]]=1;Q.push(V[x][i]);}}}return;}

//int cell[100][100]; int d[100][100],vis[100][100];int row,col;inline void bfs(int sx,int sy){ MEM(vis,0);vis[sx][sy]=1;queue<pii>q; q.push(pii(sx,sy));while(!q.empty()){pii top=q.front();q.pop();for(int k=0; k<4; k++){int tx=top.ff+fx[k];int ty=top.ss+fy[k]; if(tx>=0 and tx<row and ty>=0 and ty<col and cell[tx][ty]!=-1 and vis[tx][ty]==0){vis[tx][ty]=1;d[tx][ty]=d[top.ff][top.ss]+1;q.push(pii(tx,ty)); }}}return;}

//inline void bi_dfs(int s,int c){if(vis[s]) return;vis[s]=1;color[s]=c;REP(i,V[s].size()) dfs(V[s][i],1-c);return;}

//struct point{int name,val;bool operator <(const point &p) const{return p.val < val;}};vector<int>V[105];int dis[105],cost[105][105];priority_queue<point>Q;void Dijkstra(int s){dis[s]=0;point get;get.name=s;get.val=0;Q.push(get);while(!Q.empty()){point tmp=Q.top();Q.pop();int now=tmp.name;REP(i,V[now].size()){int x=V[now][i];if(dis[now]+cost[now][x]<dis[x]){dis[x]=dis[now]+cost[now][x];get.name=x;get.val=dis[x];Q.push(get);}}}return;}

//struct edge{int u,v,w;bool operator < (const edge &p) const{return w < p.w;}};int pr[MAX];vector<edge>e;int find(int r){return pr[r]= (pr[r]==r) ? r:find(pr[r]);}int kruskal(int n){sort(e.begin(),e.end());FOR(i,1,n) pr[i]=i;int cnt=0,sum=0;REP(i,e.size()){int x=find(e[i].u);int y=find(e[i].v);if(x!=y){pr[x]=y;cnt++;sum+=e[i].w;if(cnt==n-1) break;}}return sum;}

//inline ll GCD (ll a,ll b ) {if(a < b) swap(a, b); while ( b ) { a = a % b; swap ( a, b ); } return a;}

//int Set(int N,int pos){return N=N | (1<<pos);}

//int reset(int N,int pos){return N= N & ~(1<<pos);}

//bool check(int N,int pos){return (bool)(N & (1<<pos));}

//// ***************************************************** TEMPLATE ***************************************************** ////

int flag[1000020];

int freq[20];



struct SuffixArray {
    string a;
    int N, m;
    vector<int> SA, LCP, x, y, w, c;

    SuffixArray(string _a, int m = 256) : a(" " + _a), N(a.length()), m(m),
            SA(N), LCP(N), x(N), y(N), w(max(m, N)), c(N) {
        a[0] = 0;
        DA();
        kasaiLCP();
        #define REF(X) { rotate(X.begin(), X.begin()+1, X.end()); X.pop_back(); }
        REF(SA); REF(LCP);
        a = a.substr(1, a.size());
        for(int i = 0; i < (int) SA.size(); ++i) --SA[i];
        #undef REF
    }

    inline bool cmp (const int a, const int b, const int l) { return (y[a] == y[b] && y[a + l] == y[b + l]); }

    void Sort() {
        for(int i = 0; i < m; ++i) w[i] = 0;
        for(int i = 0; i < N; ++i) ++w[x[y[i]]];
        for(int i = 0; i < m - 1; ++i) w[i + 1] += w[i];
        for(int i = N - 1; i >= 0; --i) SA[--w[x[y[i]]]] = y[i];
    }

    void DA() {
        for(int i = 0; i < N; ++i) x[i] = a[i], y[i] = i;
        Sort();
        for(int i, j = 1, p = 1; p < N; j <<= 1, m = p) {
            for(p = 0, i = N - j; i < N; i++) y[p++] = i;
            for (int k = 0; k < N; ++k) if (SA[k] >= j) y[p++] = SA[k] - j;
            Sort();
            for(swap(x, y), p = 1, x[SA[0]] = 0, i = 1; i < N; ++i)
                x[SA[i]] = cmp(SA[i - 1], SA[i], j) ? p - 1 : p++;
        }
    }

    void kasaiLCP() {
        for (int i = 0; i < N; i++) c[SA[i]] = i;
        for (int i = 0, j, k = 0; i < N; LCP[c[i++]] = k)
            if (c[i] > 0) for (k ? k-- : 0, j = SA[c[i] - 1]; a[i + k] == a[j + k]; k++);
            else k = 0;
    }
};





int main()
{

    //fRead

    FastRead

    int k=0;
    string str="";
    string s;

    char ch='&';

    int cur=0;

    //int t=2;
    while(cin >> s)
    {
        //cin >> s;
        k++;
        int x=s.size();
        FOR(i,cur,cur+x)flag[i]=k;
        cur+=x;
        cur++;
        str+=s;
        str+=ch;
        ch++;
    }

//    cout << str << '\n';
//
//    REP(i,str.size())cout << flag[i] << ' ';
//    cout << '\n';

    SuffixArray sa(str,256);

    int n=str.size();

//    FOR(i,k,n-1)cout << sa.SA[i] << ' ';
//    cout << '\n';
//    FOR(i,k,n-1)cout << flag[sa.SA[i]] << ' ';
//    cout << '\n';
//    FOR(i,k,n-1)cout << sa.LCP[i] << ' ';
//    cout << '\n';

    deque <int> dq;

    //deque <int> :: iterator it;



    int cnt=1;
    int st=k,en=k;
    freq[flag[sa.SA[k]]]++;

    int ans=0;

    while(en<n)
    {
        if(st>en)break;

        if(cnt==k)
        {
            //cout << "********\n";
            int d=sa.SA[st];
            st++;
            //cout << st << ' ' << sa.SA[st] << ' ' << sa.LCP[st] << " **\n";
            int x=sa.LCP[st];
            d=flag[d];
            freq[d]--;
            if(freq[d]==0)cnt--;
//            for(it=dq.begin();it!=dq.end();it++)cout << *it << ' ';
//            cout << '\n';
            if(dq.front()==x)dq.pop_front();
//            for(it=dq.begin();it!=dq.end();it++)cout << *it << ' ';
//            cout << '\n';
            if(cnt==k and en<n)
            {
                //cout << "$$$$$$\n";
                int a=dq.front();
                //cout << a << '\n';
                ans=max(ans,a);
                //cout << ans << '\n';
                //cout << "$$$$$$\n";
            }
            //cout << "********\n";
        }

        if(cnt!=k)
        {
            //cout << "^^^^^^^^\n";
            en++;
            //cout << en << ' ' << sa.SA[en] << ' ' << sa.LCP[en] << " **\n";
            int x=sa.LCP[en];
            int d=sa.SA[en];
            d=flag[d];
            freq[d]++;
            if(freq[d]==1)cnt++;
//            for(it=dq.begin();it!=dq.end();it++)cout << *it << ' ';
//            cout << '\n';
            while(dq.size() and dq.back()>x)dq.pop_back();
            dq.push_back(x);
//            for(it=dq.begin();it!=dq.end();it++)cout << *it << ' ';
//            cout << '\n';
            if(cnt==k and en<n)
            {
                //cout << "!!!!!!!!!\n";
                int a=dq.front();
                //cout << a << '\n';
                ans=max(ans,a);
                //cout << ans << '\n';
                //cout << "!!!!!!!!!\n";
            }
            //cout << "^^^^^^^^\n";
        }
    }

    cout << ans;

}