Language: C++

 #include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <vector>
#include <list>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cctype>
#include <cassert>
#include <climits>
#include <string>
#include <bitset>
#include <cfloat>
#include <unordered_set>
#include <iomanip>
using namespace std;
typedef long double ld;
typedef long long int ll;
typedef unsigned long long int ull;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<char> vc;
typedef vector<bool> vb;
typedef vector<double> vd;
typedef vector<string> vs;
typedef vector<ll> vll;
typedef vector<pair<int,int> > vpii;
typedef vector<vector<int> > vvi;
typedef vector<vector<char> > vvc;
typedef vector<vector<string> > vvs;
typedef vector<vector<ll> > vvll;
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define rrep(i,n) for(int i = 1; i <= (n); ++i)
#define irep(it, stl) for(auto it = stl.begin(); it != stl.end(); it++)
#define drep(i,n) for(int i = (n) - 1; i >= 0; --i)
#define fin(ans) cout << (ans) << endl
#define mp(p,q) make_pair(p, q)
#define pb(n) push_back(n)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define Sort(a) sort(a.begin(), a.end())
#define Rort(a) sort(a.rbegin(), a.rend())
#define MATHPI acos(-1)
int dx8[8] = {1, 0, -1, 0, 1, -1, -1, 1};
int dy8[8] = {0, 1, 0, -1, 1, 1, -1, -1};
int dx4[4] = {1, 0, -1, 0};
int dy4[4] = {0, 1, 0, -1};
template <class T> inline bool chmax(T& a,T b){if(a<b){a=b;return 1;} return 0;}
template <class T> inline bool chmin(T& a,T b){if(a>b){a=b;return 1;} return 0;}
template<typename A, size_t N, typename T> void Fill(A (&array)[N], const T &val){ fill((T*)array, (T*)(array+N), val); }
struct io{io(){ios::sync_with_stdio(false);cin.tie(0);}};
const int INF = INT_MAX;
const ll LLINF = 1LL<<60;
const ll MOD = 1000000007;
const double EPS = 1e-9;


#include <functional>
template <class T>
class SegTree {
    int n;
    vector<T> data;
    T def;
    function<T(T, T)> operation;
    function<T(T, T)> update;
    T _query(int a, int b, int k, int l, int r) {
        if (r <= a || b <= l) return def;
        if (a <= l && r <= b)
        return data[k];
         else {
            T c1 = _query(a, b, 2 * k + 1, l, (l + r) / 2);
            T c2 = _query(a, b, 2 * k + 2, (l + r) / 2, r);
            return operation(c1, c2);
        }
    }
    public:
// _n:必要サイズ, _def:初期値かつ単位元, _operation:クエリ関数,
// _update:更新関数,例えば和が欲しいなら単位元は０、minならINFとか
//区間minQueryならint func(int a, int b){ return min(a, b); }みたいのをoperationに、和ならint func(int a, int b){ return a + b; }をいれる
        SegTree(size_t _n, T _def, function<T(T, T)> _operation,
            function<T(T, T)> _update)
            : def(_def), operation(_operation), update(_update) {
                n = 1;
                while (n < _n) {
                    n *= 2;
                }
                data = vector<T>(2 * n - 1, def);
        }
        void change(int i, T x) {//updateは足し合わせなら [](T d, T x){ return d + x; }更新なら[](T d, T x){ return x; }
            i += n - 1;//実際の配列のindexへ,実際の配列はセグ木の葉部分
            data[i] = update(data[i], x);//配列そのものを更新したら
            while (i > 0) {//セグ木にも伝播させて更新
                i = (i - 1) / 2;//親に伝播
                data[i] = operation(data[i * 2 + 1], data[i * 2 + 2]);
            }
        }
        T query(int a, int b) {
            return _query(a, b, 0, 0, n);
        }
        T operator[](int i) {
            return data[i + n - 1];
        }
};

//ポイントdp[i][j]とやっていくとTLEなのでどう高速化するかがポイント、LISみたいにセグメント木で区間の最大クエリを早くできるのでNをlogNに落とせばいい、BITでも可
int main(void) {
    int N; cin >> N;
    vll h(N),a(N);
    rep(i,N) cin >> h[i];
    rep(i,N) cin >> a[i];

    SegTree<ll> dp(N+1,0,[](ll a,ll b){return max(a,b);},[](ll a,ll b){return b;});

    ll res = 0;
    rep(i,N){
        ll A = st.query(0,h[i]);

        if(st.get(h[i],h[i]+1) < A+a[i]){
            st.change(h[i],A+a[i]);
            res = max(res,A+a[i]);
        }
    }

    fin(res);

}

Compiler output:
a.cc: In function 'int main()':
a.cc:119:16: error: 'st' was not declared in this scope; did you mean 'std'?
  119 |         ll A = st.query(0,h[i]);
      |                ^~
      |                std