Submission #3782514


Source Code Expand

#include<bits/stdc++.h>
#define ff(i, x, y) for(int i = x;i <= y;i++)
using namespace std;
typedef long long ll;
int n, pre[100010], mes[100010], ans, bit[200010], cnt;
ll sum;
//map<int, int>mp;
int lowbit(int x)
{
    return x&(-x);
}
void add(int i,int x)
{
    while(i<=n + 100005)
    {
        bit[i]+=x;
        i+=lowbit(i);
    }
	return;
}
void sub(int i,int x)
{
    while(i<=n + 100005)
    {
        bit[i]-=x;
        i+=lowbit(i);
    }
	return;
}
int qsum(int i)
{
    int s=0;
    while(i>0)
    {
        s+=bit[i];
        i-=lowbit(i);
    }
    return s;
}
bool check(int x) {
	ll tmp = 0;
	ff(i, 1, n) {
		if(mes[i] <= x)
			pre[i] = -1;
		else
			pre[i] = 1;
		pre[i] += pre[i - 1];
	//	bit[i] = bit[i + 100005] = 0;
	}
	ff(i, 1, 200005)
		bit[i] = 0;
	add(100005, 1);
	ff(i, 1, n) {
		tmp = tmp + i - qsum(pre[i] + 100005);
		add(pre[i] + 100005, 1);
	//	cout << tmp << endl;
	}
	//cout << "     " << x << "     " << tmp << endl;
	//cout << tmp << endl;
	if(tmp >= sum / 2 + 1)
		return true;
	return false;
}
int main() {
	scanf("%d", &n);
	sum = (n + 1);
	sum = sum * n / 2;
	ff(i, 1, n) {
		scanf("%d", &mes[i]);
		//pre[i] = mes[i];
	}
	int l = 0, r = 1e9 + 7, mid = (l + r) / 2;
	//cout << mid << endl;
	while(l <= r) {
		mid = (l + r) / 2;
		if(check(mid)) {
			ans = mid;
			r = mid - 1;
		}
		else 
			l = mid + 1;
	}
	printf("%d\n", ans);
	return 0;	
}

Submission Info

Submission Time
Task D - Median of Medians
User Acnext
Language C++14 (GCC 5.4.1)
Score 700
Code Size 1469 Byte
Status AC
Exec Time 102 ms
Memory 1792 KB

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:65:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
./Main.cpp:69:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &mes[i]);
                       ^

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 700 / 700
Status
AC × 3
AC × 19
Set Name Test Cases
Sample 0_00.txt, 0_01.txt, 0_02.txt
All 0_00.txt, 0_01.txt, 0_02.txt, 1_00.txt, 1_01.txt, 1_02.txt, 1_03.txt, 1_04.txt, 1_05.txt, 1_06.txt, 1_07.txt, 1_08.txt, 1_09.txt, 1_10.txt, 1_11.txt, 1_12.txt, 1_13.txt, 1_14.txt, 1_15.txt
Case Name Status Exec Time Memory
0_00.txt AC 4 ms 1024 KB
0_01.txt AC 4 ms 1024 KB
0_02.txt AC 4 ms 1024 KB
1_00.txt AC 4 ms 1024 KB
1_01.txt AC 4 ms 1024 KB
1_02.txt AC 77 ms 1792 KB
1_03.txt AC 79 ms 1792 KB
1_04.txt AC 79 ms 1792 KB
1_05.txt AC 78 ms 1792 KB
1_06.txt AC 79 ms 1792 KB
1_07.txt AC 78 ms 1792 KB
1_08.txt AC 102 ms 1792 KB
1_09.txt AC 102 ms 1792 KB
1_10.txt AC 101 ms 1792 KB
1_11.txt AC 101 ms 1792 KB
1_12.txt AC 99 ms 1792 KB
1_13.txt AC 102 ms 1792 KB
1_14.txt AC 101 ms 1792 KB
1_15.txt AC 101 ms 1792 KB