oj.uz

Submission #95461

# Submission time Handle Problem Language Result Execution time Memory
95461 2019-02-01T11:34:07 Z forestryks Printed Circuit Board (CEOI12_circuit) C++14
40 / 100
 53 ms 2936 KB 
///////////////////////////////////////////////////////////////////////////////////////////////
#include <bits/stdc++.h>
using namespace std;

#define mp make_pair
#define pb push_back
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define FILE_IO(x) freopen((string(x) + ".in").c_str(), "r", stdin); freopen((string(x) + ".out").c_str(), "w", stdout)
#define f first
#define s second
#define x1 x1qwer
#define y1 y1qwer
#define right right123
#define left left123
#define foreach(it, v) for (auto it : v)
#define rep(it, n) for (int it = 0; it < n; ++it)
#define forin(it, l, r) for (int it = l; it < r; ++it)
#define all(x) x.begin(), x.end()

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const double DINF = numeric_limits<double>::infinity();
const ll MOD = 1e9 + 7;
const double EPS = 1e-7;
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
mt19937 mmtw_(MOD);
uniform_int_distribution<ll> rd_;
ll randomll() { return rd_(mmtw_);}
ll rnd(ll x, ll y) { return rd_(mmtw_) % (y - x + 1) + x; }
////////////////////////////////////////////////////////////////////////////////////////////////

struct pt {
    int x, y;
    int id;
};

inline bool operator==(const pt &a, const pt &b) {
    return a.x == b.x && a.y == b.y;
}

inline pt operator-(const pt &a) {
    return {-a.x, -a.y};
}

inline pt operator-(const pt &a, const pt &b) {
    return {a.x - b.x, a.y - b.y};
}

inline ll dot(const pt &a, const pt &b) {
    return 1LL * a.x * b.x + 1LL * a.y * b.y;
}

inline ll cross(const pt &a, const pt &b) {
    return 1LL * a.x * b.y - 1LL * a.y * b.x;
}

inline ll dd0(const pt &a) {
    return dot(a, a);
}

const int MAXN = 1e5 + 5;
int n;
pt a[MAXN];
bool used[MAXN];
int ord[MAXN];

inline int md(int x) {
    if (x >= n) return x - n;
    if (x < 0) return x + n;
    return x;
}

int findLowest() {
    int s = 0;
    for (int i = 0; i < n; ++i) {
        ll cr = cross(a[i], a[s] - a[i]);
        if (cr > 0 || (cr == 0 && dd0(a[i]) < dd0(a[s]))) {
            s = i;
        }
    }
    return s;
}

int findHighest() {
    int t = 0;
    for (int i = 0; i < n; ++i) {
        ll cr = cross(a[i], a[t] - a[i]);
        if (cr < 0 || (cr == 0 && dd0(a[i]) < dd0(a[t]))) {
            t = i;
        }
    }
    return t;
}

struct cmp {
    bool operator()(int i, int j) {
        if (cross(a[i], a[j]) <= 0) {
            return cross(a[j + 1] - a[j], a[i] - a[j]) > 0;
        } else {
            return cross(a[i + 1] - a[i], a[j] - a[i]) < 0;
        }
    }
};

int main() {
    FAST_IO;
    cin >> n;
    rep(i, n) {
        cin >> a[i].x >> a[i].y;
        a[i].id = i + 1;
    }

    assert(n > 2);

    int lowest = findLowest();
    if (cross(a[md(lowest - 1)] - a[lowest], a[md(lowest + 1)] - a[lowest]) < 0) {
        reverse(a, a + n);
    }

    rotate(a, a + findLowest(), a + n);
    n = findHighest() + 1;

    for (int i = 0; i < n; ++i) {
        ord[i] = i;
    }

    sort(ord, ord + n, [](int i, int j){
        int cr = cross(a[i], a[j]);
        if (cr != 0) return cr > 0;
        return dd0(a[i]) < dd0(a[j]);
    });

    vector<int> res;
    set<int, cmp> s;
    for (int ii = 0; ii < n; ++ii) {
        int i = ord[ii];

        bool add = (i + 1 < n && cross(a[i], a[i + 1] - a[i]) > 0);

        if (used[i]) {
            s.erase(i - 1);
        }

        if (!s.empty()) {
            int f = *s.begin();
            if (cross(a[f + 1] - a[f], a[i] - a[f]) > 0) res.push_back(a[i].id);
        } else {
            res.push_back(a[i].id);
        }

        if (add) {
            s.insert(i);
            used[i + 1] = true;
        }
    }

    sort(all(res));

    cout << res.size() << '\n';
    for (auto it : res) {
        cout << it << ' ';
    }
    cout << '\n';
}

Subtask #1
40.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 504 KB Output is correct
3 Correct 3 ms 504 KB Output is correct
4 Correct 3 ms 504 KB Output is correct
5 Incorrect 7 ms 632 KB Output isn't correct
6 Incorrect 7 ms 632 KB Output isn't correct
7 Incorrect 12 ms 1016 KB Output isn't correct
8 Incorrect 5 ms 632 KB Output isn't correct
9 Correct 6 ms 636 KB Output is correct
10 Incorrect 8 ms 632 KB Output isn't correct
11 Incorrect 7 ms 760 KB Output isn't correct
12 Correct 8 ms 632 KB Output is correct
13 Incorrect 18 ms 1144 KB Output isn't correct
14 Correct 14 ms 888 KB Output is correct
15 Correct 18 ms 1144 KB Output is correct
16 Incorrect 35 ms 1912 KB Output isn't correct
17 Incorrect 53 ms 2680 KB Output isn't correct
18 Runtime error 20 ms 2936 KB Execution killed with signal 11 (could be triggered by violating memory limits)
19 Runtime error 20 ms 2808 KB Execution killed with signal 11 (could be triggered by violating memory limits)
20 Runtime error 22 ms 2808 KB Execution killed with signal 11 (could be triggered by violating memory limits)