Submission #1268000

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268000		wedonttalkanymore	Hedgehog Daniyar and Algorithms (IZhO19_sortbooks)	C++20	100 / 100	1332 ms	113124 KiB

sortbooks

#include <bits/stdc++.h>
/*
    Strat code: 
    - Thinking about how to solve the full problems: 15 min
    - Thinking about subtasks + code: 30 min
    - Stress: 10 - 15 min
    => Total need 2h15m
*/
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 = 1e6 + 5, inf = 1e18, mod = 1e9 + 7, block = 320, lim = 16;

int n, m;
int a[N];
struct queries {
    int l, k, id;
};
vector <queries> query[N];
int Left[N], ans[N];

void preprocess() {
    stack <int> st;
    for (int i = 1; i <= n; i++) {
        while(st.size() && a[st.top()] <= a[i]) st.pop();
        if (st.size()) Left[i] = st.top();
        st.push(i);
    }
    while(st.size()) st.pop();
}

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

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    if (fopen(".inp", "r")) {
        freopen(".inp", "r", stdin);
        freopen(".out", "w", stdout);
    }
    cin >> n >> m;
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= m; i++) {
        int l, r, k;
        cin >> l >> r >> k;
        query[r].push_back({l, k, i});
    }
    preprocess();
    for (int i = 1; i <= n; i++) {
        int t = Left[i];
        if (t > 0) st.update(1, 1, n, t, a[i] + a[t]);
        for (auto [l, k, id] : query[i]) {
            int tmp = st.get(1, 1, n, l, i);
            if (tmp <= k) ans[id] = 1;
            else ans[id] = 0;
        }
    }
    for (int i = 1; i <= m; i++) cout << ans[i] << '\n';
    return 0;
}

Compilation message (stderr)

sortbooks.cpp: In function 'int main()':
sortbooks.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);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
sortbooks.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: 8 / 8
• Subtask 2: 9 / 9
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 30 / 30
• Subtask 6: 23 / 23