結果

問題 No.2012 Largest Triangle
ユーザー 👑 ygussany
提出日時 2022-07-16 00:21:28
言語 C
(gcc 13.3.0)
結果
WA  
実行時間 -
コード長 3,526 bytes
コンパイル時間 426 ms
コンパイル使用メモリ 34,324 KB
実行使用メモリ 11,392 KB
最終ジャッジ日時 2024-06-27 22:14:12
合計ジャッジ時間 15,942 ms
ジャッジサーバーID
(参考情報)
judge1 / judge2
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 1
other AC * 36 WA * 5
権限があれば一括ダウンロードができます

ソースコード

diff #
プレゼンテーションモードにする

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <sys/time.h>
typedef struct {
long long x, y;
} point;
double distance(point p, point q)
{
return sqrt((double)(p.x - q.x) * (p.x - q.x) + (double)(p.y - q.y) * (p.y - q.y));
}
int is_above(point p, point q, point r)
{
if (p.x == q.x) {
if (r.x == p.x) return 0;
else if (r.x < p.x) return 1;
else return -1;
}
if (p.x == r.x) {
if (p.y < r.y) return 1;
else if (p.y > r.y) return -1;
else return 0;
}
point t;
if (q.x < p.x) {
t = q;
q = p;
p = t;
}
if ((q.y - p.y) * (r.x - p.x) < (r.y - p.y) * (q.x - p.x)) return 1;
else if ((q.y - p.y) * (r.x - p.x) > (r.y - p.y) * (q.x - p.x)) return -1;
else return 0;
}
// Twice of the area of the triangle pqr
long long area_of_triangle(point p, point q, point r)
{
long long L, R, B, T;
L = p.x;
if (L > q.x) L = q.x;
if (L > r.x) L = r.x;
R = p.x;
if (R < q.x) R = q.x;
if (R < r.x) R = r.x;
B = p.y;
if (B > q.y) B = q.y;
if (B > r.y) B = r.y;
T = p.y;
if (T < q.y) T = q.y;
if (T < r.y) T = r.y;
long long ans = (R - L) * (T - B) * 2 - (llabs(p.x - q.x) * llabs(p.y - q.y) + llabs(q.x - r.x) * llabs(q.y - r.y) + llabs(r.x - p.x) * llabs(r.y
        - p.y));
if (p.x != L && p.x != R && p.y != B && p.y != T) {
if (is_above(q, r, p) == 1) {
if ((q.x == L && q.y == B) || (q.x == R && q.y == T)) ans -= (p.x - L) * (T - p.y);
else ans -= (R - p.x) * (T - p.y);
} else {
if ((q.x == L && q.y == B) || (q.x == R && q.y == T)) ans -= (R - p.x) * (p.y - B);
else ans -= (p.x - L) * (p.y - B);
}
} else if (q.x != L && q.x != R && q.y != B && q.y != T) {
if (is_above(r, p, q) == 1) {
if ((r.x == L && r.y == B) || (r.x == R && r.y == T)) ans -= (q.x - L) * (T - q.y);
else ans -= (R - q.x) * (T - q.y);
} else {
if ((r.x == L && r.y == B) || (r.x == R && r.y == T)) ans -= (R - q.x) * (q.y - B);
else ans -= (q.x - L) * (q.y - B);
}
} else if (r.x != L && r.x != R && r.y != B && r.y != T) {
if (is_above(p, q, r) == 1) {
if ((p.x == L && p.y == B) || (p.x == R && p.y == T)) ans -= (r.x - L) * (T - r.y);
else ans -= (R - r.x) * (T - r.y);
} else {
if ((p.x == L && p.y == B) || (p.x == R && p.y == T)) ans -= (r.x - L) * (r.y - B);
else ans -= (R - r.x) * (r.y - B);
}
}
return ans;
}
typedef struct {
double key;
int id;
} data;
void merge_sort(int n, data x[])
{
static data y[200001] = {};
if (n <= 1) return;
merge_sort(n / 2, &(x[0]));
merge_sort((n + 1) / 2, &(x[n/2]));
int i, p, q;
for (i = 0, p = 0, q = n / 2; i < n; i++) {
if (p >= n / 2) y[i] = x[q++];
else if (q >= n) y[i] = x[p++];
else y[i] = (x[p].key < x[q].key)? x[p++]: x[q++];
}
for (i = 0; i < n; i++) x[i] = y[i];
}
void chmax(long long* a, long long b)
{
if (*a < b) *a = b;
}
int main()
{
struct timeval tt;
double beg, cur;
gettimeofday(&tt, NULL);
beg = tt.tv_sec + (double)tt.tv_usec / 1000000;
int i, N;
point p[200001];
data d[200001];
scanf("%d", &N);
for (i = 1, p[0].x = 0, p[0].y = 0; i <= N; i++) {
scanf("%lld %lld", &(p[i].x), &(p[i].y));
d[i-1].key = distance(p[0], p[i]);
d[i-1].id = i;
}
merge_sort(N, d);
int j;
long long ans = 0;
for (i = N - 1; i >= 0; i--) {
for (j = i - 1; j >= 0; j--) {
if (ans - d[i].key * d[j].key >= 0.0) break;
chmax(&ans, area_of_triangle(p[0], p[d[i].id], p[d[j].id]));
}
gettimeofday(&tt, NULL);
cur = tt.tv_sec + (double)tt.tv_usec / 1000000;
if (cur - beg > 2.49) break;
}
printf("%lld\n", ans);
fflush(stdout);
return 0;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0