Submission #1295699

#	Time	Username	Problem	Language	Result	Execution time	Memory
1295699		thaibeo123	3단 점프 (JOI19_jumps)	C++20	100 / 100	628 ms	68048 KiB

jumps

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

#define NAME "A"
#define ll long long
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define MASK(x) (1ll << (x))
#define BIT(x, i) (((x) >> (i)) & 1)

const int N = 5e5 + 5;

struct Node {
    int l, r, id;
};

int n, q;
int a[N], ans[N];
vector<pair<int, int>> line;
vector<pair<int, int>> que[N];

struct SegmentTree {
    vector<int> val, st, lazy;

    SegmentTree(int n): val(n << 2 | 3), st(n << 2 | 3), lazy(n << 2 | 3) {}

    void build(int l = 1, int r = n, int x = 1) {
        if (l == r) {
            val[x] = a[l];
            return;
        }
        int mid = (l + r) >> 1;
        build(l, mid, x << 1);
        build(mid + 1, r, x << 1 | 1);
        val[x] = max(val[x << 1], val[x << 1 | 1]);
    }

    void down(int x) {
        lazy[x << 1] = max(lazy[x << 1], lazy[x]);
        lazy[x << 1 | 1] = max(lazy[x << 1 | 1], lazy[x]);
        st[x << 1] = max(st[x << 1], lazy[x] + val[x << 1]);
        st[x << 1 | 1] = max(st[x << 1 | 1], lazy[x] + val[x << 1 | 1]);
    }

    void update(int u, int v, int siu, int l = 1, int r = n, int x = 1) {
        if (l > v || r < u) return;
        if (l >= u && r <= v) {
            st[x] = max(st[x], siu + val[x]);
            lazy[x] = max(lazy[x], siu);
            return;
        }

        int mid = (l + r) >> 1;
        down(x);
        if (u <= mid) update(u, v, siu, l, mid, x << 1);
        if (v > mid) update(u, v, siu, mid + 1, r, x << 1 | 1);
        st[x] = max(st[x << 1], st[x << 1 | 1]);
    }

    int get(int u, int v, int l = 1, int r = n, int x = 1) {
        if (l > v || r < u) return 0;
        if (l >= u && r <= v) return st[x];
        int mid = (l + r) >> 1;
        down(x);
        if (v <= mid) return get(u, v, l, mid, x << 1);
        if (u > mid) return get(u, v, mid + 1, r, x << 1 | 1);
        return max(get(u, v, l, mid, x << 1), get(u, v, mid + 1, r, x << 1 | 1));
    }
};

void input() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    cin >> q;
    for (int i = 1; i <= q; i++) {
        int l, r;
        cin >> l >> r;
        que[l].pb({r, i});
    }
}

void solve() {
    SegmentTree st(n);
    st.build();
    stack<int> s;
    for (int i = n; i >= 1; i--) {
        while (s.size() && a[s.top()] <= a[i]) {
            line.pb({i, s.top()});
            s.pop();
        }
        if (s.size()) {
            line.pb({i, s.top()});
        }
        s.push(i);
    }
    sort(all(line), greater<>());
    int j = 0;
    for (int i = n; i >= 1; i--) {
        while (j < (int)line.size() && line[j].fi >= i) {
            int l = line[j].fi, r = line[j].se;
            st.update(2 * r - l, n, a[l] + a[r]);
            j++;
        }
        for (auto it : que[i]) {
            int r = it.fi, id = it.se;
            ans[id] = st.get(i, r);
        }
    }
    for (int i = 1; i <= q; i++) {
        cout << ans[i] << "\n";
    }
}

signed main() {
    if (fopen(NAME".INP", "r")) {
        freopen(NAME".INP", "r", stdin);
        freopen(NAME".OUT", "w", stdout);
    }
    cin.tie(0)->sync_with_stdio(0);

    int t = 1;
    //cin >> t;
    while (t--) {
        input();
        solve();
    }

    return 0;
}

Compilation message (stderr)

jumps.cpp: In function 'int main()':
jumps.cpp:120:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  120 |         freopen(NAME".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
jumps.cpp:121:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  121 |         freopen(NAME".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 27 / 27
• Subtask 4: 54 / 54