Submission #981459

#	Time	Username	Problem	Language	Result	Execution time	Memory
981459		kh0i	Global Warming (CEOI18_glo)	C++17	100 / 100	211 ms	11932 KiB

glo

#include "bits/stdc++.h"
using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...)
#endif

using ll = long long;
using pii = pair<int, int>;

#define F first
#define S second
#define sz(x) (int)((x).size())
#define all(x) (x).begin(), (x).end()

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll get_rand(ll l, ll r) {
    assert(l <= r);
    return uniform_int_distribution<ll> (l, r)(rng);
}

struct ST{
    int n;
    vector<ll> st;

    void init(int _n){
        n = _n;
        st.clear();
        st.resize(4 * n + 6, 0);
    }

    void _update(int id, int l, int r, int pos, int val){
        if(l == r){
            st[id] = val;
            return;
        }
        int mid = (l + r) >> 1;
        if(pos <= mid)
            _update(id << 1, l, mid, pos, val);
        else
            _update(id << 1 | 1, mid + 1, r, pos, val);
        st[id] = max(st[id << 1], st[id << 1 | 1]);
    }

    int _get(int id, int l, int r, int tl, int tr){
        if(l > tr or tl > r)
            return 0;
        if(tl <= l and r <= tr)
            return st[id];
        int mid = (l + r) >> 1;
        return max(_get(id << 1, l, mid, tl, tr), _get(id << 1 | 1, mid + 1, r, tl, tr));
    }

    void update(int pos, int val){ _update(1, 1, n, pos, val); }
    int get(int l, int r) { return _get(1, 1, n, l, r); }
} st;

const int N = 2e5 + 3;

int n, x, t[N], tc[N], f[N];
vector<int> xx;

void solve(){
    cin >> n >> x;
    for(int i = 1; i <= n; ++i){
        cin >> t[i];
        xx.push_back(t[i]);
    }
    xx.push_back(0);
    sort(all(xx));
    xx.resize(unique(all(xx)) - xx.begin());

    st.init(N);

    for(int i = n; i >= 1; --i){
        tc[i] = lower_bound(all(xx), t[i]) - xx.begin();
        f[i] = st.get(tc[i] + 1, N) + 1;
        st.update(tc[i], f[i]);
    }

    int res = *max_element(f + 1, f + n + 1);
    st.init(N);

    for(int i = 1; i <= n; ++i){
        int bound = upper_bound(all(xx), t[i] + x - 1) - xx.begin() - 1;
        res = max(res, st.get(1, bound) + f[i]);

        st.update(tc[i], st.get(1, tc[i] - 1) + 1);
    }

    cout << res;
}

int32_t main() {
    cin.tie(nullptr)->sync_with_stdio(0);
    #define task "troll"
    if(fopen(task".inp", "r")){
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int test = 1;
//    cin >> test;
    for(int i = 1; i <= test; ++i){
//        cout << "Case #" << i << ": ";
        solve();
    }
    #ifdef LOCAL
        cerr << "\n[Time]: " << 1000.0 * clock() / CLOCKS_PER_SEC << " ms.\n";
    #endif
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int32_t main()':
glo.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:101:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• 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