Submission #859343

#	Time	Username	Problem	Language	Result	Execution time	Memory
859343		wii	Triple Jump (JOI19_jumps)	C++17	0 / 100	123 ms	41024 KiB

jumps

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace __gnu_pbds;
using namespace std;

typedef double db;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;

#define X first
#define Y second
#define gcd __gcd
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define bit(i, mask) ((mask) >> (i) & 1)
#define reset(x, val) memset(x, val, sizeof(x))
#define foru(i,a,b) for(int i = (a); i <= (b); ++i)
#define ford(i,a,b) for(int i = (a); i >= (b); --i)
#define FastIO ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);

template<typename T> bool maximize(T &res, const T &val) { if (res < val) { res = val; return true; } return false; }
template<typename T> bool minimize(T &res, const T &val) { if (val < res) { res = val; return true; } return false; }

const ll Linf = 0x3f3f3f3f3f3f3f3f;
const int Inf = 0x3f3f3f3f;
const ll Mod = 1e9 + 7;
const ll Mod2 = ll(1e9) + 9;
const int Lim = 1e6 + 5;
const int inv6 = 166666668;

// #define Sieve
#ifdef Sieve
    vector<int> pr;
    vector<int> lpf;
    void Linear_sieve(int n = Lim) {
        pr.assign(1, 2);
        lpf.assign(n + 1, 2);

        for (int x = 3; x <= n; x += 2) {
            if (lpf[x] == 2) pr.push_back(lpf[x] = x);
            for (int i = 1; i < pr.size() && pr[i] <= lpf[x] && pr[i] * x <= n; ++i)
                lpf[pr[i] * x] = pr[i];
        }
    }
#endif

// #define Ckn_calc
#ifdef Ckn_calc
    const int LIM = 1e6 + 16;

    int fact[LIM + 10]; /// factorial:         fact[n] = n!
    int invs[LIM + 10]; /// inverse modular:   invs[n] = n^(-1)
    int tcaf[LIM + 10]; /// inverse factorial: tcaf[n] = (n!)^(-1)
    void precal_nck(int n = LIM)
    {
        fact[0] = fact[1] = 1;
        invs[0] = invs[1] = 1;
        tcaf[0] = tcaf[1] = 1;
        for (int i = 2; i <= n; ++i)
        {
            fact[i] = (1LL * fact[i - 1] * i) % Mod;
            invs[i] = Mod - 1LL * (Mod / i) * invs[Mod % i] % Mod;
            tcaf[i] = (1LL * tcaf[i - 1] * invs[i]) % Mod;
        }
    }

    ll C(int n, int k) {
        if (n < k || k < 0) return 0;

        ll res = fact[n];
        res *= tcaf[k], res %= Mod;
        res *= tcaf[n - k], res %= Mod;
        return res;
    }

    ll P(int n, int k) {
        ll res = fact[n];
        res *= tcaf[n - k], res %= Mod;
        return res;
    }
#endif

/// ====*====*====*====*====*====*====*====*====*====*====*====*====*====*====*====*====

const int base = 3;
const int N = 5e5 + 5;
const int K = log2(N) + 2;
const int dx[] = {+1, -1, 0, 0};
const int dy[] = {0, 0, +1, -1};
const int block_size = sqrt(2e9) + 2;

int n;
int a[N];

vector<pii> qs[N];
vector<pii> upd[N];

pii f[N * 4];
int lazy[N * 4];

#define lx (id << 1)
#define rx (lx | 1)
pii combine(pii l, pii r) {
    return make_pair(max(l.first, r.first), max(l.second, r.second));
}

void push(int id, int val) {
    maximize(f[id].first, f[id].second + val);
    maximize(lazy[id], val);
}

void down(int id) {
    push(lx, lazy[id]);
    push(rx, lazy[id]);
    lazy[id] = 0;
}

void build(int l = 1, int r = n, int id = 1) {
    if (l == r) {
        return f[id] = make_pair(a[l], a[l]), void();
    }

    int mid = (l + r) >> 1;
    build(l, mid, lx);
    build(mid + 1, r, rx);

    f[id] = combine(f[lx], f[rx]);
}

void update(int u, int v, int x, int l = 1, int r = n, int id = 1) {
    if (r < u || v < l) return;
    if (u <= l && r <= v)
        return push(id, x);
    
    down(id);
    int mid = (l + r) >> 1;

    update(u, v, x, l, mid, lx);
    update(u, v, x, mid + 1, r, rx);

    f[id] = combine(f[lx], f[rx]);
}

int get(int u, int v, int l = 1, int r = n, int id = 1) {
    if (r < u || v < l) return 0;
    if (u <= l && r <= v)
        return f[id].first;
    
    down(id);
    int mid = (l + r) >> 1;

    return max(get(u, v, l, mid, lx), get(u, v, mid + 1, r, rx));
}

int ans[N];
void solve() {
    cin >> n;
    foru(i, 1, n) cin >> a[i];

    int q; cin >> q;
    foru(i, 1, q) {
        int l, r;
        cin >> l >> r;
        qs[l].pb({r, i});
    }

    build();

    vector<int> d;
    foru(i, 1, n) {
        while (!d.empty()) {
            int j = d.back();

            if (i * 2 - j)
                upd[j].pb({i * 2 - j, a[i] + a[j]});
            
            if (a[i] > a[j]) break;
            d.pop_back();
        }

        d.push_back(i);
    }

    ford(i, n, 1) {
        for (auto &[x, y]: upd[i]) {
            update(x, n, y);

            // cout << x << " " << n << " " << y << "\n";
        }

        for (auto &[r, id]: qs[i]) {
            ans[id] = get(i, r);
        }

        
    }

    foru(i, 1, q) cout << ans[i] << "\n";
}

signed main() {
    FastIO;

    #define task "test"
    if (fopen(task".inp", "r")) {
		freopen(task".inp", "r", stdin);
		freopen(task".out", "w", stdout);
	}

    #ifdef Sieve
        Linear_sieve();
    #endif

    #ifdef Ckn_calc
        precal_nck();
    #endif

    int ntest = 1;
    // cin >> ntest;
    while (ntest--) {
        //cout << "Case " << q << ": " << "\n"; 
        solve();
        cout << "\n";
    }

    return 0;
}

/**  /\_/\
 *  (= ._.)
 *  / >TL \>AC
**/

Compilation message (stderr)

jumps.cpp: In function 'int main()':
jumps.cpp:208:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  208 |   freopen(task".inp", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
jumps.cpp:209:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  209 |   freopen(task".out", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 27
• Subtask 4: 0 / 54