@@ -8,6 +8,11 @@ struct ranking {
88 ll second;
99};
1010
11+ // P[i][j] holds the ranking of the j-th suffix
12+ // after comparing the first 2^i characters
13+ // of that suffix
14+ ll P[20 ][1000000 ];
15+ 1116bool comp (ranking a, ranking b) {
1217 if (a.first == b.first ) {
1318 return a.second < b.second ;
@@ -22,11 +27,6 @@ vector<ll> build_suffix_array(string s) {
2227 // vector to hold final suffix array result
2328 vector<ll> sa (n);
2429
25- // P[i][j] holds the ranking of the j-th suffix
26- // after comparing the first 2^i characters
27- // of that suffix
28- ll P[lgn][n];
29- 3030 // vector to store ranking tuples of suffixes
3131 vector<ranking> ranks (n);
3232
@@ -58,12 +58,34 @@ vector<ll> build_suffix_array(string s) {
5858 return sa;
5959}
6060
61+ vector<ll> build_lcp (vector<ll> &sa, ll n) {
62+ 63+ vector<ll> lcp (n,0 );
64+ ll k, i, j , x, delta, step = ceil (log2 (n));
65+ for (k = 1 ; k < n; k++) {
66+ i = k;
67+ j = k - 1 ;
68+ for (x = step; x >= 0 ; x--) {
69+ if (P[x][sa[i]] == P[x][sa[j]]) {
70+ delta = pow (2 ,x);
71+ lcp[i] += delta;
72+ i += delta;
73+ j += delta;
74+ }
75+ }
76+ }
77+ return lcp;
78+ }
79+ 6180int main () {
6281 string s;
82+ ll i, n, m, ans;
6383 cin >> s;
84+ n = s.length ();
6485 vector<ll> sa = build_suffix_array (s);
65- for (ll i = 0 ; i < s.length (); i++) {
66- cout << i << " : "
86+ vector<ll> lcp = build_lcp (sa,n);
87+ for (ll i = 0 ; i < n; i++) {
88+ cout << i << " : " " : " substr (sa[i]) << " : "
6789 }
6890 return 0 ;
6991}
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