oj.uz

Submission #151348

# Submission time Handle Problem Language Result Execution time Memory
151348 2019-09-02T14:18:53 Z theboatman Bigger segments (IZhO19_segments) C++17
0 / 100
 2 ms 504 KB 
#include <bits/stdc++.h>

#define y1 theboatman
#define make_struct(args...) {args}

#define int ll

using namespace std;

typedef long long ll;

const long long INF = 1e18 + 10;
const int inf = 1e9 + 10;
const int N = 1e6 + 10;

struct tree {
    struct node {
        int mx, add;
    };

    int v, tl, tr;
    vector <node> t;

    void build(int n) {
         v = 1;
         tl = 0;
         tr = n - 1;

         t.assign(n * 10, make_struct(-inf, -inf));
    }

    void push(int v, int deep) {
        if (deep == 2) {
            return;
        }

        t[v * 2].add = max(t[v * 2].add, t[v].add);
        t[v * 2 + 1].add = max(t[v * 2 + 1].add, t[v].add);

        push(v * 2, deep + 1);
        push(v * 2 + 1, deep + 1);
    }

    void modify(int v, int tl, int tr, int l, int r, int x) {
        if (l > r) {
            return;
        }

        if (tl == l && tr == r) {
            t[v].add = max(t[v].add, x);
            return;
        }

        int tm = (tl + tr) / 2;
        modify(v * 2, tl, tm, l, min(r, tm), x);
        modify(v * 2 + 1, tm + 1, tr, max(l, tm + 1), r, x);
    }

    int get(int v, int tl, int tr, int pos) {
        push(v, 0);

        if (tl == tr) {
            return t[v].add;
        }

        int tm = (tl + tr) / 2;
        if (pos <= tm) {
            return get(v * 2, tl, tm, pos);
        }
        else {
            return get(v * 2 + 1, tm + 1, tr, pos);
        }
    }

    int get(int pos) {
        return get(v, tl, tr, pos);
    }

    void modify(int l, int r, int x) {
        modify(v, tl, tr, l, r, x);
    }
};

tree dp[3010];
vector <int> pref;

int get(int l, int r) {
    int res = pref[r];

    return (l ? res - pref[l - 1] : res);
}

int32_t main() {
    cin.tie(0);
    ios::sync_with_stdio(0);

    int n;
    cin >> n;

    vector <int> a(n);
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }

    for(int i = 0; i < n; i++) {
        dp[i].build(n);
    }

    dp[0].modify(0, n - 1, 1);

    pref.resize(n);
    for(int i = 0; i < n; i++) {
        pref[i] = (i ? pref[i - 1] + a[i] : a[i]);
    }


    for(int i = 0; i < n; i++) {
        for(int j = i; j < n; j++) {
            int l = j + 1, r = n;
            while(l < r) {
                int c = (l + r) / 2;
                if (get(i, j) > get(j + 1, c)) {
                    l = c + 1;
                }
                else {
                    r = c;
                }
            }

            l = j + 1;
            while(l < n && get(i, j) > get(j + 1, l)) {
                l++;
            }

            //cout << i << " " << j << " " << dp[i].get(j) + 1 << " " << l << " " << n - 1 << "\n";
            dp[j + 1].modify(l, n - 1, dp[i].get(j) + 1);
        }
    }

    int ans = 0;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            ans = max(ans, dp[i].get(j));
        }
    }

    cout << ans << "\n";
    return 0;
}
/*
*/

Subtask #1
0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 504 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Incorrect 2 ms 504 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 504 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Incorrect 2 ms 504 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #3
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 504 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Incorrect 2 ms 504 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #4
0 / 36.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 504 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Incorrect 2 ms 504 KB Output isn't correct
5 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 504 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Incorrect 2 ms 504 KB Output isn't correct
5 Halted 0 ms 0 KB -