Add a bunch of other problems.

ITMO Academy: pilot course - Suffix Array - Step 2/A. Suffix Array - 2.cpp

@@ -0,0 +1,172 @@
+/* Problem URL: https://codeforces.com/edu/course/2/lesson/2/2/practice/contest/269103/problem/A */
+
+#include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
+{
+
+}
+
+#define TEST 0
+
+void solve()
+{
+    string a;
+    cin >> a;
+
+    a.push_back('$');
+
+    int n = a.size();
+
+    vi p(n);
+    vi c(max(256, n));
+    rep(i, n) {
+        c[a[i]]++;
+    }
+
+    nrep(i, 1, c.size()) {
+        c[i] += c[i - 1];
+    }
+
+    rep(i, n) {
+        c[a[i]]--;
+        p[c[a[i]]] = i;
+    }
+
+    vi suf(n);
+    suf[p[0]] = 0;
+    nrep(i, 1, n) {
+        suf[p[i]] = suf[p[i - 1]];
+        if (a[p[i]] != a[p[i - 1]]) {
+            suf[p[i]]++;
+        }
+    }
+
+    vi pn(n);
+    vi cn(c.size());
+    for (int j = 0; (1 << j) < n; j++) {
+        rep(i, n) {
+            pn[i] = p[i] - (1 << j);
+            pn[i] += n * (pn[i] < 0);
+        }
+
+        fill(all(c), 0);
+
+        rep(i, n) {
+            c[suf[pn[i]]]++;
+        }
+
+        nrep(i, 1, c.size()) {
+            c[i] += c[i - 1];
+        }
+
+        for (int i = n - 1; i >= 0; i--) {
+            c[suf[pn[i]]]--;
+            p[c[suf[pn[i]]]] = pn[i];
+        }
+
+        cn[p[0]] = 0;
+        nrep(i, 1, n) {
+            pair<int, int> cur = {suf[p[i]], suf[(p[i] + (1 << j)) % n]};
+            pair<int, int> prev = {suf[p[i - 1]], suf[(p[i - 1] + (1 << j)) % n]};
+            cn[p[i]] = cn[p[i - 1]];
+            if (cur != prev) {
+                cn[p[i]]++;
+            }
+        }
+        swap(suf, cn);
+    }
+
+    cout << p;
+}
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    pre();
+
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
+    }
+}