Submission #926313

#	Time	Username	Problem	Language	Result	Execution time	Memory
926313		VMaksimoski008	Global Warming (CEOI18_glo)	C++14	100 / 100	485 ms	28540 KiB

glo

#include <bits/stdc++.h>
#define all(x) x.begin(), x.end()
using namespace std;
 
struct SegTree {
    int n;
    vector<int> tree;
 
    SegTree(int _n) {
        n = _n;
        tree.resize(4*n+5);
    }
 
    void update(int u, int tl, int tr, int pos, int val) {
        if(tl == tr) {
            tree[u] = max(tree[u], val);
        } else {
            int tm = (tl + tr) / 2;
            if(pos <= tm)
                update(2*u, tl, tm, pos, val);
            else
                update(2*u+1, tm+1, tr, pos, val);
            tree[u] = max(tree[2*u], tree[2*u+1]);
        }
    }
 
    int query(int u, int tl, int tr, int l, int r) {
        if(tl > tr || l > tr || tl > r) return 0;
        if(l <= tl && tr <= r) return tree[u];
        int tm = (tl + tr) / 2;
        return max(
            query(2*u, tl, tm, l, r),
            query(2*u+1, tm+1, tr, l, r)
        );
    }
 
    void update(int p, int v) { update(1, 0, n-1, p, v); }
    int query(int l, int r) { return query(1, 0, n-1, l, r); }
    void reset() { for(int i=0; i<tree.size(); i++) tree[i] = 0; }
};
 
int32_t main() {
    int n, X, ans = 0;
    cin >> n >> X;
 
    set<int> s;
    vector<int> v(n+1);
 
    for(int i=1; i<=n; i++) {
        cin >> v[i];
        s.insert(v[i]); s.insert(v[i] - X);
    }
 
    vector<int> comp(all(s));
 
    SegTree tree(2*n+5);
 
    vector<int> L(n+1);
    for(int i=1; i<=n; i++) {
        int p = lower_bound(all(comp), v[i]) - comp.begin();
        L[i] = tree.query(0, p-1) + 1;
        tree.update(p, L[i]);
    }
 
    tree.reset();
    for(int i=n; i>=1; i--) {
        int p = lower_bound(all(comp), v[i] - X) - comp.begin();
        int lis = tree.query(p+1, 2*n-1) + 1;
        ans = max(ans, L[i] + lis - 1);
        p = lower_bound(all(comp), v[i]) - comp.begin();
        tree.update(p, tree.query(p+1, 2*n-1) + 1);
    }
 
    cout << ans << '\n';
    return 0;
}

Compilation message (stderr)

glo.cpp: In member function 'void SegTree::reset()':
glo.cpp:39:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     void reset() { for(int i=0; i<tree.size(); i++) tree[i] = 0; }
      |                                 ~^~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 20 / 20
• Subtask 6: 17 / 17
• Subtask 7: 25 / 25