func_code_string: #include <bits/stdc++.h>   using namespace std;   mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());   inline int rand(int x, int y) {     ++y;     return (rng() % (y - x)) + x;   }   int n, k, A[300006], dp[35006][56];   vector<pair<int, int> > v;   struct node {     int second, e, m;     int v = 0;     node *l, *r;     node(int _s, int _e, bool prog) {       second = _s, e = _e, m = (second + e) / 2;       v = 0;       if (second != e && prog) {         l = new node(second, m, 1);         r = new node(m + 1, e, 1);       } else         l = NULL, r = NULL;     }     node *update(int x, int nv) {       node *tmp = new node(second, e, 0);       if (second == e) {         assert(v == 0);         tmp->v = v + nv;         return tmp;       }       if (x > m) {         tmp->l = l;         assert(r != NULL);         tmp->r = r->update(x, nv);       } else {         assert(l != NULL);         tmp->l = l->update(x, nv);         tmp->r = r;       }       tmp->v = tmp->l->v + tmp->r->v;       return tmp;     }     int rmq(int x, int y) {       if (second == x && e == y) return v;       if (x > m)         return r->rmq(x, y);       else if (y <= m)         return l->rmq(x, y);       else         return l->rmq(x, m) + r->rmq(m + 1, y);     }   } * seg[35006];   int ubdd(pair<int, int> x) {     int st = -1, en = v.size(), mid = 0;     while (en - st > 1) {       mid = (st + en) >> 1;       if (x.first > v[mid].first)         en = mid;       else         st = mid;     }     return en + 1;   }   unordered_map<int, int> mp[35006];   int RMQ(int x, int y) {     if (mp[y].count(x)) return mp[y][x];     auto itr = ubdd(pair<int, int>(y + 1, -(long long)1e18)) - 1;     return mp[y][x] = (itr > 0 ? seg[itr]->rmq(x, y) : 0);     set<int> second;     for (int i = x; i < y + 1; i++) second.insert(A[i]);     return second.size();   }   void dnc(int st, int en, int x, int y, int k) {     if (st > en) return;     int opt_pos = x;     int mid = (st + en) / 2;     for (int i = min(y, mid); i >= x; i--) {       if (dp[mid][k] < dp[i - 1][k - 1] + RMQ(i, mid)) {         opt_pos = i;         dp[mid][k] = dp[i - 1][k - 1] + RMQ(i, mid);       }     }     if (st < mid) dnc(st, mid - 1, x, opt_pos, k);     if (mid < en) dnc(mid + 1, en, opt_pos, y, k);   }   vector<int> val[35006];   void solve() {     for (int i = 1; i < n + 1; i++) {       assert(A[i] <= 35000);       val[A[i]].push_back(i);     }     for (int i = 1; i < n + 1; i++) {       val[A[i]].push_back(n + 1);     }     for (int i = 1; i < n + 1; i++)       v.push_back(pair<int, int>(           *upper_bound((val[A[i]]).begin(), (val[A[i]]).end(), i), i));     sort((v).begin(), (v).end(), greater<pair<int, int> >());     seg[0] = new node(1, n + 1, 1);     for (int i = 0; i < v.size(); i++) {       seg[i + 1] = seg[i]->update(v[i].second, 1);     }     return;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cin >> n >> k;     for (int i = 1; i < n + 1; i++) cin >> A[i];     solve();     unordered_set<int> second;     for (int i = 1; i < n + 1; i++) {       second.insert(A[i]);       dp[i][1] = second.size();     }     for (int i = 2; i < k + 1; i++) {       dnc(1, n, 1, n, i);     }     cout << dp[n][k] <<   n ;   }   