Submission #1256073

#	Time	Username	Problem	Language	Result	Execution time	Memory
1256073		wedonttalkanymore	Worst Reporter 2 (JOI16_worst_reporter2)	C++20	0 / 100	16 ms	34880 KiB

worst_reporter2

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define int long long
#define pii pair<ll, ll>
#define fi first
#define se second

const ll N = 4e5 + 5, inf = 1e18, mod = 1e9 + 7, block = 320, lim = 1 << 16;

int n;
pii a[N], b[N];
vector<int> comp;
vector<int> color[N];

struct ST {
    vector<int> st, lz;
    ST (int _n) {
        st.assign(4 * (_n + 1), 0);
        lz.assign(4 * (_n + 1), 0);
    }
    void lazy(int i, int l, int r) {
        if (lz[i] != 0) {
            if (l < r) {
                st[2 * i] += lz[i];
                st[2 * i + 1] += lz[i];
                lz[2 * i] += lz[i];
                lz[2 * i + 1] += lz[i];
            }
            lz[i] = 0;
        }
    }
    void update(int i, int l, int r, int u, int v, int val) {
        if (u > r || v < l) return;
        if (u <= l && r <= v) {
            st[i] += val;
            lz[i] += val;
            return;
        }
        lazy(i, l, r);
        int mid = (l + r) / 2;
        update(2 * i, l, mid, u, v, val);
        update(2 * i + 1, mid + 1, r, u, v, val);
        st[i] = min(st[2 * i], st[2 * i + 1]);
    }
    int get(int i, int l, int r, int u, int v) {
        lazy(i, l, r);
        if (u > r || v < l) return inf;
        if (u <= l && r <= v) return st[i];
        int mid = (l + r) / 2;
        return min(get(2 * i, l, mid, u, v), get(2 * i + 1, mid + 1, r, u, v));
    }
} st(N);

bool cmp(pii x, pii y) {
    return x.se < y.se;
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    if (fopen(".inp", "r")) {
        freopen(".inp", "r", stdin);
        freopen(".out", "w", stdout);
    }
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i].fi >> a[i].se;
    for (int i = 1; i <= n; i++) cin >> b[i].fi >> b[i].se;
    for (int i = 1; i <= n; i++) {
        comp.push_back(a[i].se);
        comp.push_back(b[i].se);
    }
    sort(comp.begin(), comp.end());
    comp.erase(unique(comp.begin(), comp.end()), comp.end());
    for (int i = 1; i <= n; i++) {
        a[i].se = lower_bound(comp.begin(), comp.end(), a[i].se) - comp.begin() + 1;
        b[i].se = lower_bound(comp.begin(), comp.end(), b[i].se) - comp.begin() + 1;
    }
    sort(a + 1, a + n + 1, cmp);
    sort(b + 1, b + n + 1, cmp);
    int sz = comp.size();
    int ptr = 0, res = 0;
    vector<int> added;
    vector<char> used(n + 2, 0);

    auto use_last_or_fallback = [&](int fallback_coord) {
        while (!added.empty() && used[added.back()]) added.pop_back();
        if (added.empty()) {
            st.update(1, 1, sz, fallback_coord, sz, -1);
            res++;
        } else {
            int idx = added.back(); added.pop_back();
            st.update(1, 1, sz, a[idx].se, sz, -1);
            // remove idx from color[a[idx].fi] safely
            auto &vc = color[a[idx].fi];
            if (!vc.empty() && vc.back() == idx) vc.pop_back();
            else {
                for (int j = (int)vc.size() - 1; j >= 0; --j) {
                    if (vc[j] == idx) { vc.erase(vc.begin() + j); break; }
                }
            }
            used[idx] = 1;
            res++;
        }
    };

    for (int i = 1; i <= n; i++) {
        while (ptr + 1 <= n && a[ptr + 1].se <= b[i].se) {
            ptr++;
            st.update(1, 1, sz, a[ptr].se, sz, 1);
            color[a[ptr].fi].push_back(ptr);
            added.push_back(ptr);
        }
        if (!color[b[i].fi].empty()) {
            int idx = color[b[i].fi].back();
            if (st.get(1, 1, sz, a[idx].se, sz) > 0) {
                st.update(1, 1, sz, a[idx].se, sz, -1);
                color[b[i].fi].pop_back();
                used[idx] = 1;
            } else {
                use_last_or_fallback(b[i].se);
            }
        } else {
            use_last_or_fallback(b[i].se);
        }
    }
    cout << res;
    return 0;
}

Compilation message (stderr)

worst_reporter2.cpp: In function 'int main()':
worst_reporter2.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen(".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
worst_reporter2.cpp:65:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |         freopen(".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 15
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40