oj.uz

Submission #95457

# Submission time Handle Problem Language Result Execution time Memory
95457 2019-02-01T10:17:39 Z forestryks Printed Circuit Board (CEOI12_circuit) C++14
40 / 100
 100 ms 2940 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];

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 seg {
    pt a, b;
};
seg s[MAXN];

bool inter(const pt &a, const seg &b) {
    if (a == b.a || a == b.b) return false;
    if (!(cross(a, b.b) >= 0 && cross(a, b.a) <= 0)) return false;
    if (!(cross(b.b - b.a, a - b.a) <= 0 && cross(b.b - b.a, -b.a) >= 0)) return false;
    return true;
}

bool check(const pt &a) {
    for (int i = 0; i < n; ++i) {
        if (inter(a, s[i])) return false;
    }
    return true;
}

vector<int> solve() {
    vector<int> res;

    for (int i = 0; i < n; ++i) {
        if (check(s[i].a)) res.push_back(s[i].a.id);
        if (check(s[i].b)) res.push_back(s[i].b.id);
    }

    sort(all(res));
    res.erase(unique(all(res)), res.end());
    return res;
}

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;

    int sz = 0;
    for (int i = 0; i + 1 < n; ++i) {
        if (cross(a[i], a[i + 1] - a[i]) > 0) s[sz++] = {a[i], a[i + 1]};
    }
    n = sz;

    vector<int> ans = solve();

    cout << ans.size() << '\n';
    for (auto it : ans) {
        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 376 KB Output is correct
3 Correct 63 ms 508 KB Output is correct
4 Execution timed out 137 ms 632 KB Time limit exceeded
5 Correct 60 ms 632 KB Output is correct
6 Correct 59 ms 504 KB Output is correct
7 Execution timed out 262 ms 860 KB Time limit exceeded
8 Correct 26 ms 504 KB Output is correct
9 Execution timed out 111 ms 632 KB Time limit exceeded
10 Correct 73 ms 732 KB Output is correct
11 Correct 76 ms 732 KB Output is correct
12 Execution timed out 128 ms 760 KB Time limit exceeded
13 Execution timed out 373 ms 1144 KB Time limit exceeded
14 Execution timed out 264 ms 1144 KB Time limit exceeded
15 Execution timed out 547 ms 1528 KB Time limit exceeded
16 Execution timed out 1076 ms 2552 KB Time limit exceeded
17 Execution timed out 1068 ms 2168 KB Time limit exceeded
18 Runtime error 21 ms 2940 KB Execution killed with signal 11 (could be triggered by violating memory limits)
19 Runtime error 21 ms 2936 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)