1+ string s;
2+ int n;
3+ 4+ struct node {
5+ int l, r, par, link;
6+ map<char,int> next;
7+ 8+ node (int l=0, int r=0, int par=-1)
9+ : l(l), r(r), par(par), link(-1) {}
10+ int len() { return r - l; }
11+ int &get (char c) {
12+ if (!next.count(c)) next[c] = -1;
13+ return next[c];
14+ }
15+ };
16+ node t[MAXN];
17+ int sz;
18+ 19+ struct state {
20+ int v, pos;
21+ state (int v, int pos) : v(v), pos(pos) {}
22+ };
23+ state ptr (0, 0);
24+ 25+ state go (state st, int l, int r) {
26+ while (l < r)
27+ if (st.pos == t[st.v].len()) {
28+ st = state (t[st.v].get( s[l] ), 0);
29+ if (st.v == -1) return st;
30+ }
31+ else {
32+ if (s[ t[st.v].l + st.pos ] != s[l])
33+ return state (-1, -1);
34+ if (r-l < t[st.v].len() - st.pos)
35+ return state (st.v, st.pos + r-l);
36+ l += t[st.v].len() - st.pos;
37+ st.pos = t[st.v].len();
38+ }
39+ return st;
40+ }
41+ 42+ int split (state st) {
43+ if (st.pos == t[st.v].len())
44+ return st.v;
45+ if (st.pos == 0)
46+ return t[st.v].par;
47+ node v = t[st.v];
48+ int id = sz++;
49+ t[id] = node (v.l, v.l+st.pos, v.par);
50+ t[v.par].get( s[v.l] ) = id;
51+ t[id].get( s[v.l+st.pos] ) = st.v;
52+ t[st.v].par = id;
53+ t[st.v].l += st.pos;
54+ return id;
55+ }
56+ 57+ int get_link (int v) {
58+ if (t[v].link != -1) return t[v].link;
59+ if (t[v].par == -1) return 0;
60+ int to = get_link (t[v].par);
61+ return t[v].link = split (go (state(to,t[to].len()), t[v].l + (t[v].par==0), t[v].r));
62+ }
63+ 64+ void tree_extend (int pos) {
65+ for(;;) {
66+ state nptr = go (ptr, pos, pos+1);
67+ if (nptr.v != -1) {
68+ ptr = nptr;
69+ return;
70+ }
71+ 72+ int mid = split (ptr);
73+ int leaf = sz++;
74+ t[leaf] = node (pos, n, mid);
75+ t[mid].get( s[pos] ) = leaf;
76+ 77+ ptr.v = get_link (mid);
78+ ptr.pos = t[ptr.v].len();
79+ if (!mid) break;
80+ }
81+ }
82+ 83+ void build_tree() {
84+ sz = 1;
85+ for (int i=0; i<n; ++i)
86+ tree_extend (i);
87+ }
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