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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#557101#6403. Master of PolygonpandapythonerWA 341ms27328kbC++237.3kb2024-09-11 03:09:362024-09-11 03:09:36

Judging History

你现在查看的是最新测评结果

  • [2024-09-11 03:09:36]
  • 评测
  • 测评结果:WA
  • 用时:341ms
  • 内存:27328kb
  • [2024-09-11 03:09:36]
  • 提交

answer

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

using ll = long long;
using ld = long double;


#define len(a) int((a).size())
#define all(a) begin(a), end(a)
#define rep(i, n) for (int i = 0; i < (n); i++)



mt19937 rnd(234234);
ld pi = atan2l(0, -1);
double eps = 1e-7;

struct vec {
    ll x, y;

    vec() {}
    vec(ll x, ll y) : x(x), y(y) {}


    bool operator==(const vec& other) const {
        return x == other.x and y == other.y;
    }
};


vec operator+(const vec& a, const vec& b) {
    return vec{ a.x + b.x, a.y + b.y };
}


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


ll operator*(const vec& a, const vec& b) {
    return a.x * b.x + a.y * b.y;
}


ll operator%(const vec& a, const vec& b) {
    return a.x * b.y - a.y * b.x;
}


ll sign(ll x) {
    if (x > 0) return 1;
    if (x < 0) return -1;
    return 0;
}

bool intersects(const vec& a, const vec& b, const vec& c, const vec& d) {
    if ((a - b) % (c - d) == 0) {
        if ((c - a) % (d - a) != 0) return false;
        if (max(a.x, b.x) < min(c.x, d.x) or max(c.x, d.x) < min(a.x, b.x)) return false;
        if (max(a.y, b.y) < min(c.y, d.y) or max(c.y, d.y) < min(a.y, b.y)) return false;
        return true;
    }
    if (sign((b - a) % (c - a)) * sign((b - a) % (d - a)) > 0) return false;
    if (sign((d - c) % (a - c)) * sign((d - c) % (b - c)) > 0) return false;
    return true;
}


int n, q;
vector<vec> poly;
vector<pair<vec, vec>> tests;
vector<int> result;


void solve_slow() {
    result.resize(q);
    rep(i, q) {
        auto& [a, b] = tests[i];
        result[i] = false;
        rep(j, n) {
            auto& c = poly[j];
            auto& d = poly[j == n - 1 ? 0 : j + 1];
            if (intersects(a, b, c, d)) {
                result[i] = true;
                break;
            }
        }
    }
}


double get(const vec& a, const vec& b, ll x) {
    if (a.x == b.x) return a.y;
    return a.y + (double(x - a.x)) / (b.x - a.x) * (b.y - a.y);
}


vector<int> sift_ind(vector<int> ind) {
    vector<int> result;
}


vector<pair<vec, vec>> pull_lines(const vector<vector<vec>>& curves, ll xl, ll xr) {
    vector<pair<vec, vec>> result;
    for (auto& curve : curves) {
        for (int i = 0; i + 1 < len(curve); i += 1) {
            vec a = curve[i], b = curve[i + 1];
            if (make_pair(a.x, a.y) < make_pair(b.x, b.y)) swap(a, b);
            if (a.x <= xl and b.x >= xr) {
                result.push_back(make_pair(a, b));
            }
        }
    }
    return result;
}


vector<vector<vec>> cut_curves(const vector<vector<vec>>& curves, ll xl, ll xr) {
    vector<vector<vec>> result;
    for (auto& curve : curves) {
        for (int l = 0; l < len(curve); l += 1) {
            if (curve[l].x < xl or curve[l].x > xr) continue;
            int r = l;
            while (r + 1 < len(curve) and (xl <= curve[r + 1].x and curve[r + 1].x <= xr)) {
                r += 1;
            }
            int nl = max(0, l - 1);
            int nr = min(r + 1, len(curve) - 1);
            result.push_back(vector<vec>(curve.begin() + nl, curve.begin() + nr + 1));
            l = r;
        }
    }
    return result;
}


void solve_rec(vector<vector<vec>> curves, vector<int> ind, ll xl, ll xr) {
    vector<int> new_ind;
    for (auto i : ind) {
        if (!result[i] and tests[i].second.x >= xl and tests[i].first.x <= xr) new_ind.push_back(i);
    }
    ind = new_ind;
    new_ind.clear();
    if (curves.empty() or ind.empty()) {
        return;
    }
    auto lines = pull_lines(curves, xl, xr);
    curves = cut_curves(curves, xl, xr);
    sort(all(lines), [&](const pair<vec, vec>& a, const pair<vec, vec>& b) {
        if (a.first == b.first) {
            return (a.second - a.first) % (b.second - b.first) > 0;
        }
        return get(a.first, a.second, xl) + eps < get(b.first, b.second, xl);
        });
    auto get_pos = [&](const vec& a) {
        int tl = -1;
        int tr = len(lines);
        while (tl + 1 < tr) {
            int tm = (tl + tr) / 2;
            auto& [c, d] = lines[tm];
            if (c.x == d.x) {
                if (a.y < c.y) {
                    tl = tm;
                } else {
                    tr = tm;
                }
            } else {
                if ((d - c) % (a - c) > 0) {
                    tl = tm;
                } else {
                    tr = tm;
                }
            }
        }
        return tl;
        };
    if (!lines.empty()) {
        for (auto i : ind) {
            auto& [a, b] = tests[i];
            int pos = -1;
            if (a.x >= xl and a.x <= xr) {
                pos = get_pos(a);
            } else if (b.x >= xl and b.x <= xr) {
                pos = get_pos(b);
            } else {
                assert(a.x < xl and b.x > xr);
                int tl = -1;
                int tr = len(lines);
                while (tl + 1 < tr) {
                    int tm = (tl + tr) / 2;
                    auto& [c, d] = lines[tm];
                    if (get(c, d, xl) + eps < get(a, b, xl)) {
                        tl = tm;
                    } else {
                        tr = tm;
                    }
                }
                pos = tl;
            }
            if (pos >= 0) {
                if (intersects(a, b, lines[pos].first, lines[pos].second)) {
                    result[i] = true;
                }
            }
            if (pos + 1 < len(lines)) {
                if (intersects(a, b, lines[pos + 1].first, lines[pos + 1].second)) {
                    result[i] = true;
                }
            }
            if (!result[i]) {
                new_ind.push_back(i);
            }
        }
        ind = new_ind;
        new_ind.clear();
    }
    if (xl == xr) {
        return;
    }
    if (xl + 1 == xr) {
        solve_rec(curves, ind, xl, xl);
        solve_rec(curves, ind, xr, xr);
        return;
    }
    ll xm = (xl + xr) / 2;
    solve_rec(curves, ind, xl, xm);
    solve_rec(curves, ind, xm, xr);
}


void solve() {
    result.assign(q, false);
    vector<vector<vec>> curves = { poly };
    curves.front().push_back(poly.front());
    vector<int> ind(q);
    rep(i, q) ind[i] = i;
    solve_rec(curves, ind, 0, 30000);
}


bool good_coord(ll x) {
    return 0 <= x and x <= 30000;
}


signed main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n >> q;
    poly.resize(n);
    rep(i, n) {
        cin >> poly[i].x >> poly[i].y;
        assert(good_coord(poly[i].x));
    }
    tests.resize(q);
    rep(i, q) {
        cin >> tests[i].first.x >> tests[i].first.y >> tests[i].second.x >> tests[i].second.y;
        assert(good_coord(tests[i].first.x));
        assert(good_coord(tests[i].second.x));
        if (make_pair(tests[i].first.x, tests[i].first.y) > 
            make_pair(tests[i].second.x, tests[i].second.y)) {
            swap(tests[i].first, tests[i].second);
        }
    }
    solve();
    rep(i, q) {
        if (result[i]) {
            cout << "YES" << "\n";
        } else {
            cout << "NO" << "\n";
        }
    }
    return 0;
}


/*
4 6
1 1
4 1
4 4
1 4
0 2 2 0
0 1 1 1
0 0 5 5
2 2 4 2
2 2 3 2
5 1 0 2

*/

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 3632kb

input:

4 6
1 1
4 1
4 4
1 4
0 2 2 0
0 1 1 1
0 0 5 5
2 2 4 2
2 2 3 2
5 1 0 2

output:

YES
YES
YES
YES
NO
YES

result:

ok 6 token(s): yes count is 5, no count is 1

Test #2:

score: -100
Wrong Answer
time: 341ms
memory: 27328kb

input:

20 200000
8838 9219
12190 11292
15953 7581
16690 6159
21104 5484
8978 1076
4354 1065
1261 676
12684 14159
15469 22416
13493 28027
15531 26837
18253 26053
26444 24253
22160 19958
24879 12856
28793 22156
25300 10245
14749 15078
12946 13942
26544 28338 18806 21279
5592 29200 20935 25253
28189 17513 215...

output:

NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
...

result:

wrong answer expected YES, found NO [1st token]