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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
#185074#2380. 中位数wosile1001323ms5872kbC++767b2023-09-21 09:48:072023-09-21 12:23:28

answer

#include<bits/stdc++.h>
#define N (n+n+1)
#define lowbit(x) (x&(-x))
using namespace std;
int n;
int a[300005];
int b[300005];
int c[600005];
void add(int x){
	while(x<=N){
		c[x]++;
		x+=lowbit(x);
	}
}
int query(int x){
	int sum=0;
	while(x){
		sum+=c[x];
		x-=lowbit(x);
	}
	return sum;
}
bool check(int x){
	b[0]=n+1;
	memset(c,0,sizeof(c));
	for(int i=1;i<=n;i++)b[i]=b[i-1]+(a[i]>x?-1:1);
	long long tot=0;
	for(int i=0;i<=n;i++){
		tot+=query(b[i]);
		add(b[i]);
	}
	return tot>=(1LL*n*(n+1)/2+1)/2;
}
int main(){
	scanf("%d",&n);
	for(int i=1;i<=n;i++)scanf("%d",&a[i]);
	int L=0,R=1e9+5,ans=1e9+5;
	while(L<=R){
		int mid=(L+R)/2;
		if(check(mid))R=mid-1,ans=mid;
		else L=mid+1;
	}
	printf("%d",ans);
	return 0;
}

详细

小提示:点击横条可展开更详细的信息

Test #1:

score: 10
Accepted
time: 0ms
memory: 3544kb

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: 3540kb

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: 3544kb

input:

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

output:

420852999

result:

ok 1 number(s): "420852999"

Test #4:

score: 10
Accepted
time: 9ms
memory: 3572kb

input:

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

output:

465193387

result:

ok 1 number(s): "465193387"

Test #5:

score: 10
Accepted
time: 9ms
memory: 3576kb

input:

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

output:

466892796

result:

ok 1 number(s): "466892796"

Test #6:

score: 10
Accepted
time: 4ms
memory: 3572kb

input:

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

output:

470507384

result:

ok 1 number(s): "470507384"

Test #7:

score: 10
Accepted
time: 327ms
memory: 5872kb

input:

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

output:

463539280

result:

ok 1 number(s): "463539280"

Test #8:

score: 10
Accepted
time: 316ms
memory: 5868kb

input:

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

output:

462334620

result:

ok 1 number(s): "462334620"

Test #9:

score: 10
Accepted
time: 323ms
memory: 5872kb

input:

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

output:

464162969

result:

ok 1 number(s): "464162969"

Test #10:

score: 10
Accepted
time: 329ms
memory: 5872kb

input:

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

output:

463577194

result:

ok 1 number(s): "463577194"

Extra Test:

score: 0
Extra Test Passed