Submission #809749

#	Time	Username	Problem	Language	Result	Execution time	Memory
809749		fanwen	Divide and conquer (IZhO14_divide)	C++17	0 / 100	1 ms	340 KiB

divide

#include <bits/stdc++.h>

using namespace std;

#define MASK(x) (1LL << (x))
#define BIT(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end()
#define REP(i, n) for (int i = 0, _n = n; i < _n; ++i)
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
#define FORE(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define debug(...) "[" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }

template <class A, class B> bool minimize(A &a, B b)  { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b)  { if (a < b) { a = b; return true; } return false; }

const int MAXN = 1e5 + 5;
const long long INF = 1e18;
int N, x[MAXN];
long long dp[MAXN], d[MAXN], g[MAXN];

struct segment_tree {
    vector <long long> it;
    segment_tree(int n = 0) : it(n << 2 | 1, INF) {}

    void update(int idx, int l, int r, int u, long long val) {
        if(l > u || r < u) return;
        if(l == r) return void(it[idx] = val);
        int mid = l + r >> 1;
        update(idx << 1, l, mid, u, val);
        update(idx << 1 | 1, mid + 1, r, u, val);
        it[idx] = min(it[idx << 1], it[idx << 1 | 1]);
    }

    int find(int idx, int l, int r, long long val) {
        if(l == r) return l;
        int mid = l + r >> 1;
        return it[idx << 1] <= val ? find(idx << 1, l, mid, val) : find(idx << 1 | 1, mid + 1, r, val);
    }
};

void you_make_it(void) {
    cin >> N;
    long long res = 0;
    FOR(i, 1, N) {
        cin >> x[i] >> g[i] >> d[i];
        maximize(res, g[i]);
        d[i] += d[i - 1];
        g[i] += g[i - 1];
    }
    segment_tree it(N);
    it.update(1, 1, N, 1, -x[1]);
    FOR(i, 2, N) {
        int j = it.find(1, 1, N, d[i] - x[i]);
        maximize(res, g[i] - g[j - 1]);
    }
    cout << res;
}

signed main() {

#ifdef LOCAL
    freopen("TASK.inp", "r", stdin);
    freopen("TASK.out", "w", stdout);
#endif
    auto start_time = chrono::steady_clock::now();

    cin.tie(0), cout.tie(0) -> sync_with_stdio(0);

    you_make_it();

    auto end_time = chrono::steady_clock::now();

    cerr << "\nExecution time : " << chrono::duration_cast <chrono::milliseconds> (end_time - start_time).count() << "[ms]" << endl;

    return (0 ^ 0);
}

// Dream it. Wish it. Do it.

Compilation message (stderr)

divide.cpp: In member function 'void segment_tree::update(int, int, int, int, long long int)':
divide.cpp:30:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   30 |         int mid = l + r >> 1;
      |                   ~~^~~
divide.cpp: In member function 'int segment_tree::find(int, int, int, long long int)':
divide.cpp:38:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   38 |         int mid = l + r >> 1;
      |                   ~~^~~

• Subtask 1: 0 / 17
• Subtask 2: 0 / 31
• Subtask 3: 0 / 52