Submission #872992

#	Time	Username	Problem	Language	Result	Execution time	Memory
872992		NeroZein	Triple Jump (JOI19_jumps)	C++17	100 / 100	769 ms	89680 KiB

jumps

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

#ifdef Nero
#include "Deb.h"
#else
#define deb(...)
#endif

const int N = 5e5 + 5;

struct node {
  int ans;
  int ab, c;
};

node seg[N * 2]; 

node merge(const node& lx, const node& rx) {
  node ret;
  ret.ans = max(lx.ans, rx.ans); 
  if (lx.ab) {
    ret.ans = max(ret.ans, lx.ab + rx.c); 
  }
  ret.ab = max(lx.ab, rx.ab);
  ret.c = max(lx.c, rx.c); 
  return ret;
}

void build(int nd, int l, int r, const vector<int>& c) {
  if (l == r) {
    seg[nd].c = c[l];
    return;
  }
  int mid = (l + r) >> 1;
  int rs = nd + ((mid - l + 1) << 1);
  build(nd + 1, l, mid, c);
  build(rs, mid + 1, r, c);
  seg[nd].c = max(seg[nd + 1].c, seg[rs].c); 
}

void upd(int nd, int l, int r, int p, int v) {
  if (l == r) {
    seg[nd].ab = max(seg[nd].ab, v);
    seg[nd].ans = max(seg[nd].ans, seg[nd].ab + seg[nd].c); 
    return; 
  }
  int mid = (l + r) >> 1;
  int rs = nd + ((mid - l + 1) << 1);
  if (p <= mid) {
    upd(nd + 1, l, mid, p, v);
  } else {
    upd(rs, mid + 1, r, p, v); 
  }
  seg[nd] = merge(seg[nd + 1], seg[rs]); 
}

node qry(int nd, int l, int r, int s, int e) {
  if (l >= s && r <= e) {
    return seg[nd]; 
  }
  int mid = (l + r) >> 1;
  int rs = nd + ((mid - l + 1) << 1);
  node ret;
  if (mid >= e) {
    ret = qry(nd + 1, l, mid, s, e);
  } else {
    if (mid < s) {
      ret = qry(rs, mid + 1, r, s, e); 
    } else {
      ret = merge(qry(nd + 1, l, mid, s, e), qry(rs, mid + 1, r, s, e)); 
    }
  }
  return ret; 
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int n;
  cin >> n;
  vector<int> a(n); 
  for (int i = 0; i < n; ++i) {
    cin >> a[i]; 
  }
  build(0, 0, n - 1, a); 
  vector<vector<pair<int, int>>> vec(n); 
  stack<int> stk; 
  for (int i = 0; i < n; ++i) {
    while (!stk.empty() && a[stk.top()] < a[i]) {
      if (2 * i - stk.top() < n) {
        vec[stk.top()].emplace_back(2 * i - stk.top(), a[i] + a[stk.top()]);
      }
      stk.pop(); 
    }
    if (!stk.empty()) {
      if (2 * i - stk.top() < n) {
        vec[stk.top()].emplace_back(2 * i - stk.top(), a[i] + a[stk.top()]);
      }
    }
    stk.push(i); 
  }
  int q;
  cin >> q; 
  vector<int> ans(q); 
  vector<vector<pair<int, int>>> qs(n); 
  for (int i = 0; i < q; ++i) {
    int l, r;
    cin >> l >> r;
    --l, --r;
    qs[l].emplace_back(r, i); 
  }
  for (int l = n - 1; l >= 0; --l) {
    for (auto [p, s] : vec[l]) {
      upd(0, 0, n - 1, p, s); 
    }
    for (auto [r, i] : qs[l]) {
      ans[i] = qry(0, 0, n - 1, 0, r).ans; 
    }
  }
  for (int i = 0; i < q; ++i) {
    cout << ans[i] << '\n'; 
  }
  return 0;
}

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