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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#673952#5276. K-Shaped FiguresIllusionaryDominance#WA 0ms3540kbC++203.3kb2024-10-25 12:17:262024-10-25 12:17:26

Judging History

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  • [2024-10-25 12:17:26]
  • 评测
  • 测评结果:WA
  • 用时:0ms
  • 内存:3540kb
  • [2024-10-25 12:17:26]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;
using pii = pair <int, int>;

inline int untitled(const pii &a) {
    if (a.first < 0) {
        // x < 0
        return a.second < 0 ? 3 : 2;
    }else {
        return a.second < 0 ? 4 : 1;
    }
}

inline bool cmp(const pii &a, const pii &b) {
    int a_ = untitled(a), b_ = untitled(b);
    if (a_ != b_) return a_ < b_;
    // dya / dxa < dyb / dxb
    return 1ll * a.second * b.first < 1ll * a.first * b.second;
}

const int MAX_N = 1000 + 5;

int N;
struct Segment{
    int x1, y1, x2, y2;
    Segment (int x1_ = 0, int y1_ = 0, int x2_ = 0, int y2_ = 0) : x1(x1_), y1(y1_), x2(x2_), y2(y2_) {}
    inline bool operator < (const Segment &comp) const {
        return cmp(pair(x2 - x1, y2 - y1), pair(comp.x2 - comp.x1, comp.y2 - comp.y1));
        // return atan2(y2 - y1, x2 - x1) < atan2(comp.y2 - comp.y1, comp.x2 - comp.x1);
    }
}seg[MAX_N];
pii node[MAX_N << 1];

inline bool check(const Segment &seg, int x0, int y0) {
    int dx1 = x0 - seg.x1, dy1 = x0 - seg.y1;
    int dx2 = seg.x2 - x0, dy2 = seg.y2 - y0;
    // dy1 / dx1 = dy2 / dx2
    return 1ll * dy1 * dx2 == 1ll * dx1 * dy2;
}

void solve() {
    cin >> N;
    for (int i = 1; i <= N; i ++) {
        int x1, y1, x2, y2;
        cin >> x1 >> y1 >> x2 >> y2;
        node[i] = pair(x1, y1);
        node[i + N] = pair(x2, y2);
        seg[i] = Segment(x1, y1, x2, y2);
    }
    int ans = 0;
    sort(node + 1, node + (N << 1) + 1);
    int M = unique(node + 1, node + (N << 1) + 1) - node - 1;
    for (int i = 1; i <= M; i ++) {
        auto [x0, y0] = node[i];
        vector <Segment> seg1;
        vector <pii> seg2;
        for (int j = 1; j <= N; j ++) {
            if (seg[j].x1 == x0 && seg[j].y1 == y0) {
                seg2.emplace_back(seg[j].x2 - seg[j].x1, seg[j].y2 - seg[j].y1);
            }else if (seg[j].x2 == x0 && seg[j].y2 == y0) {
                seg2.emplace_back(seg[j].x1 - seg[j].x2, seg[j].y1 - seg[j].y2);
            }else if (check(seg[j], x0, y0)) {
                seg1.push_back(seg[j]);
            }
        }
        if (!(seg1.empty() || seg2.empty())) {
            sort(seg1.begin(), seg1.end());
            sort(seg2.begin(), seg2.end(), cmp);
            auto ed = unique(seg2.begin(), seg2.end());
            int n = ed - seg2.begin();
            int i = 0, j = n - 1;
            for (int k = 0; k < (int)seg1.size(); k ++) {
                pii dir0 = pair(seg1[k].x2 - seg1[k].x1, seg1[k].y2 - seg1[k].y1);
                pii dir1 = pair(seg1[k].x1 - seg1[k].x2, seg1[k].y1 - seg1[k].y2);
                if (cmp(dir0, seg2[i])) i = 0;
                if (cmp(seg2[j], dir1)) j = n - 1;
                // i < dir0, j > dir1
                while (i < n && cmp(seg2[i], dir0)) i ++;
                if (i == n) i --;
                while (j >= 0 && cmp(dir1, seg2[j])) j --;
                if (j < 0) j ++;
                int cnt0 = i <= j ? j - i + 1 : n - (i - j - 1), cnt1 = n - cnt0;
                ans += (cnt0 * (cnt0 - 1) + cnt1 * (cnt1 - 1)) / 2;
            }
        }
    }
    cout << ans << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    
    int T; cin >> T;
    while (T --) solve();
    
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3508kb

input:

2
5
0 0 0 10
0 5 3 10
0 5 3 0
0 5 7 4
0 5 6 2
8
0 0 10 10
3 4 4 4
4 4 4 5
3 4 4 4
7 7 7 8
7 7 8 7
5 5 4 6
5 5 3 7

output:

6
2

result:

ok 2 number(s): "6 2"

Test #2:

score: -100
Wrong Answer
time: 0ms
memory: 3540kb

input:

10
3
-1 -1 0 -1
-1 -1 0 -1
-1 -1 1 1
3
1 -1 0 0
0 -1 1 1
0 1 1 -1
3
0 -1 1 1
-1 1 1 -1
1 1 -1 0
3
-1 0 0 1
-1 1 0 1
-1 1 -1 0
3
-1 1 1 1
1 0 0 -1
1 -1 -1 0
3
0 -1 0 0
1 -1 0 0
-1 -1 1 1
3
1 0 1 1
1 -1 1 0
0 -1 -1 0
3
1 1 0 -1
-1 0 0 1
0 1 -1 0
3
1 0 0 -1
1 0 1 -1
1 0 0 0
3
-1 -1 -1 0
1 -1 1 0
1 0 0 -1

output:

0
0
0
0
0
0
0
0
0
0

result:

wrong answer 6th numbers differ - expected: '1', found: '0'