Submission #998572

#	Time	Username	Problem	Language	Result	Execution time	Memory
998572		Beerus13	Triple Jump (JOI19_jumps)	C++17	100 / 100	811 ms	78804 KiB

jumps

#include<bits/stdc++.h>
using namespace std;
#define FOR(i, a, b)  for(int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, b, a) for(int i = (b), _a = (a); i >= _a; --i)
#define REP(i, a, b)  for(int i = (a), _b = (b); i < _b;  ++i)
#define REPD(i, b, a) for(int i = (b), _a = (a); i > _a;  --i)
#define MASK(i) (1LL << (i))
#define BIT(mask, i) (((mask) >> (i)) & 1)
#define __builtin_popcount __builtin_popcountll
#define all(v) v.begin(), v.end()
#define ll long long
#define ull unsigned long long
#define pii pair<int, int>
#define fi first
#define se second
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll Rand(ll l, ll r) {return l + (ull) rng() % (r - l + 1);}

template<class X, class Y>
    bool minimize(X &x, const Y &y) {
        if (x > y) {
            x = y;
            return true;
        } else return false;
    }
template<class X, class Y>
    bool maximize(X &x, const Y &y) {
        if (x < y) {
            x = y;
            return true;
        } else return false;
    }
template<class T>
    T Abs(const T &x) {
        return (x < 0 ? -x : x);
    }

const int N = 5e5 + 5;
const int inf = 1e9;

struct node {
    int res, mx, lz;
    node() {
        res = mx = lz = 0;
    }
};

int n, q, a[N];
vector<pii> qrs[N];
vector<pii> candidates;
node st[N << 2];

void push(int id, int x) {
    maximize(st[id].lz, x);
    maximize(st[id].res, st[id].mx + x);
}

void down(int id) {
    if(!st[id].lz) return;
    push(id << 1, st[id].lz);
    push(id << 1 | 1, st[id].lz);
    st[id].lz = 0; 
}

void upd_point(int u, int x) {
    int id = 1, l = 1, r = n;
    while(l ^ r) {
        down(id);
        int m = l + r >> 1;
        if(u > m) id = id << 1 | 1, l = m + 1;
        else id = id << 1, r = m;
    }
    st[id].mx = x;
    while(id > 1) id >>= 1, st[id].mx = max(st[id << 1].mx, st[id << 1 | 1].mx);
}

void update(int u, int v, int x, int id = 1, int l = 1, int r = n) {
    if(u > r || v < l) return;
    if(u <= l && r <= v) {
        push(id, x);
        return;
    }
    down(id);
    int m = l + r >> 1;
    update(u, v, x, id << 1, l, m);
    update(u, v, x, id << 1 | 1, m + 1, r);
    st[id].res = max(st[id << 1].res, st[id << 1 | 1].res);
}

int query(int u, int v, int id = 1, int l = 1, int r = n) {
    if(u > r || v < l) return 0;
    if(u <= l && r <= v) return st[id].res;
    down(id);
    int m = l + r >> 1;
    return max(query(u, v, id << 1, l, m), query(u, v, id << 1 | 1, m + 1, r));
}

void process() {
    cin >> n;
    FOR(i, 1, n) cin >> a[i];
    cin >> q;
    REP(i, 0, q) {
        int l, r; cin >> l >> r;
        qrs[l].emplace_back(r, i);
    }
    
    vector<int> stk;
    FOR(i, 1, n) {
        while(!stk.empty() && a[stk.back()] < a[i]) stk.pop_back();
        if(stk.size()) candidates.emplace_back(stk.back(), i);
        stk.push_back(i);
    }
    while(!stk.empty()) stk.pop_back();
    FORD(i, n, 1) {
        while(!stk.empty() && a[stk.back()] < a[i]) stk.pop_back();
        if(stk.size()) candidates.emplace_back(i, stk.back());
        stk.push_back(i);
    }

    sort(all(candidates));
    vector<int> ans(q);

    FORD(i, n, 1) {
        upd_point(i, a[i]);
        while(!candidates.empty() && candidates.back().fi == i) {
            auto [l, r] = candidates.back(); candidates.pop_back();
            update(2 * r - l, n, a[l] + a[r]);
        }
        for(auto [r, id] : qrs[i]) {
            ans[id] = query(i, r);
        }
    }
    for(auto x : ans) cout << x << '\n';
}

signed main() {
    if(fopen("test.inp","r")) {
        freopen("test.inp","r",stdin);
        freopen("test.out","w",stdout);
    }
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int ntests = 1;
    // cin >> ntests;
    while(ntests--) process();
    return 0;
}


// https://oj.uz/problem/view/JOI19_jumps

Compilation message (stderr)

jumps.cpp: In function 'void upd_point(int, int)':
jumps.cpp:69:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   69 |         int m = l + r >> 1;
      |                 ~~^~~
jumps.cpp: In function 'void update(int, int, int, int, int, int)':
jumps.cpp:84:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   84 |     int m = l + r >> 1;
      |             ~~^~~
jumps.cpp: In function 'int query(int, int, int, int, int)':
jumps.cpp:94:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   94 |     int m = l + r >> 1;
      |             ~~^~~
jumps.cpp: In function 'int main()':
jumps.cpp:138:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  138 |         freopen("test.inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
jumps.cpp:139:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  139 |         freopen("test.out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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