제출 #48440

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
48440		aleksami	Vudu (COCI15_vudu)	C++14	140 / 140	426 ms	65536 KiB

vudu

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
#define MAXN 1000005
ll a[MAXN];
int bit[MAXN];

void update(int idx,int val)
{
	while(idx < MAXN)
	{
		bit[idx]+=val;
		idx+=idx&(-idx);
	}
}
int get(int idx)
{
	int s=0;
	while(idx > 0)
	{
		s+=bit[idx];
		idx-=idx&(-idx);
	}
	return s;
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int n;
	cin >> n;
	for(int i = 1; i <= n; i++)
	{
		cin >> a[i];
	}
	vector <ll> v;
	ll p;
	cin >> p;
	for(int i = 1; i <= n; i++)a[i]-=p;
	for(int i = 1; i <= n; i++)
	{
		a[i]+=a[i-1];
		v.push_back(a[i]);
	}
	v.push_back(0LL);
	sort(v.begin(),v.end());
	v.erase(unique(v.begin(),v.end()),v.end());
	ll ans = 0LL;
	for(int i = 0; i <= n; i++)
	{
		a[i]=lower_bound(v.begin(),v.end(),a[i])-v.begin()+1;
		if(i>0)update(a[i-1],1);
		ans += get(a[i]);
	}
	cout << ans;
	return 0;
}

• Subtask 1: 140 / 140