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NOI.AC

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#213986#2380. 中位数huangyuhe40879ms1460kbC++111.3kb2024-11-14 21:17:142024-11-14 23:07:41

answer

#include <bits/stdc++.h>
#define C__ const
#define int long long
using namespace std;
C__ int N_ = 2e5 + 10, inf = 0x3f3f3f3f3f3f3f3fLL;
int n, m, a[N_], b[N_];
signed main() {
	cin >> n;
	for (int i = 1; i <= n; i++) cin >> a[i];
	for (int i = 1; i <= n; i++) {
		priority_queue<pair<int, int> > que1;
		priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > que2;
		que1.push({-inf, 0}), que2.push({inf, 0});
		for (int j = i; j <= n; j++) {
			int x = a[j], y = j;
			if ((j - i) & 1) {
				if (x < que1.top().first) {
					que1.push({x, y});
					x = que1.top().first, y = que1.top().second;
					que1.pop();
				}
				que2.push({x, y});
			} else {
				if (x > que2.top().first) {
					que2.push({x, y});
					x = que2.top().first, y = que2.top().second;
					que2.pop();
				}
				que1.push({x, y});
			}
			++b[que1.top().second];
		}
	}
	vector<int> idx(n);
	iota(idx.begin(), idx.end(), 1);
	sort(idx.begin(), idx.end(), [&](int i, int j) { return a[i] < a[j]; } );
	for (int c = 0; c < (int) idx.size(); c++)
		if (c > 0) b[idx[c]] += b[idx[c - 1]];
	m = (b[idx[n - 1]] + 1) / 2;
	int l = 0, r = n - 1;
	while (l < r) {
		int mid = l + (r - l) / 2;
		if (b[idx[mid]] < m) l = mid + 1;
		else r = mid;
	}
	cout << a[idx[l]] << "\n";
	return 0;
}

Details

小提示:点击横条可展开更详细的信息

Test #1:

score: 10
Accepted
time: 3ms
memory: 1268kb

input:

200
247837946 222748444 549404903 934970141 181690491 116150147 755881953 912914845 578004877 589768...

output:

411892743

result:

ok 1 number(s): "411892743"

Test #2:

score: 10
Accepted
time: 3ms
memory: 1268kb

input:

200
504553675 321343511 781936447 172776833 779139954 643752948 106 164 303976944 828799931 11502170...

output:

451369372

result:

ok 1 number(s): "451369372"

Test #3:

score: 10
Accepted
time: 3ms
memory: 1268kb

input:

200
738368650 91602659 340556191 835209882 409442204 656938221 258295858 90658347 126689369 56196859...

output:

420852999

result:

ok 1 number(s): "420852999"

Test #4:

score: 0
Time Limit Exceeded

input:

5000
300051244 685920750 122806687 315801142 33592358 339985437 262520930 380010194 687330910 550362...

output:


result:


Test #5:

score: 10
Accepted
time: 870ms
memory: 1460kb

input:

5000
108135249 950186870 146626753 682580494 744412491 4159 995071655 157947560 668940645 878891308 ...

output:

466892796

result:

ok 1 number(s): "466892796"

Test #6:

score: 0
Time Limit Exceeded

input:

5000
246610103 780664789 678774940 716124165 518453378 300121008 135383319 939869983 430946660 13412...

output:


result:


Test #7:

score: 0
Runtime Error

input:

300000
786856547 380253059 684225515 795392038 881780483 18437791 793783577 832330260 801624996 3466...

output:


result:


Test #8:

score: 0
Runtime Error

input:

300000
951000485 930070933 3566360 157114366 150196488 611226665 123590886 950624066 472150346 57976...

output:


result:


Test #9:

score: 0
Runtime Error

input:

300000
728509094 406128756 696166390 756254976 31403187 672131182 35544213 870708756 3659210 5227553...

output:


result:


Test #10:

score: 0
Runtime Error

input:

300000
804874490 52247250 546638789 400214210 383796618 47995083 814777769 507157584 466189162 28296...

output:


result: