Submission #22880

#	Time	Username	Problem	Language	Result	Execution time	Memory
22880		Lazy Against The Machine (#40)	Donut-shaped Enclosure (KRIII5_DE)	C++14	2 / 7	1500 ms	80552 KiB

DE

#include <bits/stdc++.h>
using namespace std;

// example implementation of sum tree
constexpr int TSIZE = 2097152; // always 2^k form && n <= TSIZE
int segtree[TSIZE * 2];
int prop[TSIZE * 2];
void seg_relax(int nod, int l, int r) {
    if (prop[nod] == 0) return;
    if (l < r) {
        int m = (l + r) >> 1;
        segtree[nod << 1] += prop[nod];
        prop[nod << 1] += prop[nod];
        segtree[nod << 1 | 1] += prop[nod];
        prop[nod << 1 | 1] += prop[nod];
    }
    prop[nod] = 0;
}
void seg_update(int nod, int l, int r, int s, int e, int val) {
    if (r < s || e < l) return;
    if (s <= l && r <= e) {
        segtree[nod] += val;
        prop[nod] += val;
        return;
    }
    seg_relax(nod, l, r);
    int m = (l + r) >> 1;
    seg_update(nod << 1, l, m, s, e, val);
    seg_update(nod << 1 | 1, m + 1, r, s, e, val);
    segtree[nod] = max(segtree[nod << 1], segtree[nod << 1 | 1]);
}
// usage:
// seg_update(1, 0, n - 1, qs, qe, val);
// seg_query(1, 0, n - 1, qs, qe);

vector<int> xcrd;
int n, l, r;
map<pair<int, int>, vector<tuple<int, int, int>>> events;

void add_seg(int x, int val, int big, int sub)
{
    int L = (lower_bound(xcrd.begin(), xcrd.end(), x - (big ? r : l)) - xcrd.begin()) * 3 + 1;
    int R = (lower_bound(xcrd.begin(), xcrd.end(), x + (big ? r : l)) - xcrd.begin()) * 3 + 1;

    if (big)
    {
        seg_update(1, 0, TSIZE - 1, L, R, val * (sub ? -1 : 1));
    }
    else
    {
        seg_update(1, 0, TSIZE - 1, L + 1, R - 1, val * (sub ? -1 : 1));
    }
}

int main()
{
    scanf("%d%d%d",&n,&l,&r);

    for (int i = 0; i < n; i++)
    {
        int x, y, val;
        scanf("%d%d%d",&x,&y,&val);
        xcrd.push_back(x - l);
        xcrd.push_back(x + l);
        xcrd.push_back(x - r);
        xcrd.push_back(x + r);
        events[{y - r, 0}].emplace_back(x, val, 1);
        events[{y - l, 1}].emplace_back(x, val, 0);
        events[{y + l, 0}].emplace_back(x, val, 0);
        events[{y + r, 1}].emplace_back(x, val, 1);
    }

    sort(xcrd.begin(), xcrd.end());
    xcrd.erase(unique(xcrd.begin(), xcrd.end()), xcrd.end());

    int ans = 0;

    for (auto &&e : events)
    {
        for (auto &&elem : e.second)
        {
            int x, val, big;
            tie(x, val, big) = elem;
            add_seg(x, val, big, e.first.second);
        }

        ans = max(ans, segtree[1]);
    }

    printf("%d\n", ans);
}

Compilation message (stderr)

DE.cpp: In function 'void seg_relax(int, int, int)':
DE.cpp:11:13: warning: unused variable 'm' [-Wunused-variable]
         int m = (l + r) >> 1;
             ^
DE.cpp: In function 'int main()':
DE.cpp:57:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d",&n,&l,&r);
                             ^
DE.cpp:62:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&x,&y,&val);
                                   ^

• Subtask 1: 2 / 2
• Subtask 2: 0 / 5