Submission #1227272

#	Time	Username	Problem	Language	Result	Execution time	Memory
1227272		ByeWorld	Vudu (COCI15_vudu)	C++20	140 / 140	234 ms	31736 KiB

vudu

#include <bits/stdc++.h>
// #pragma GCC optimize("O3")
#define int long long
#define ll long long
#define se second
#define fi first
#define pb push_back
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
using namespace std;
typedef pair<int,int> pii;
typedef pair<pii,pii> ipii;
const int MAXN = 1e6+10;
const int SQRT = 450;
const int INF = 2e18;
const int MOD = 235813;
const int LOG = 32;
int sum(int a, int b){ return (a+MOD+b)%MOD; }
void chsum(int &a, int b){ a = (a+MOD+b)%MOD; }
int mul(int a, int b){ return (a*b)%MOD; }
void chmul(int &a, int b){ a = (a*b)%MOD; }
int expo(int a, int b){
	if(b==0) return 1;
	int te = expo(a, b/2); te = mul(te,te);
	return (b%2 ? mul(te,a) : te);
}
void chmn(auto &a, auto b){ a = min(a, b); }
void chmx(auto &a, auto b){ a = max(a, b); }

int n, a[MAXN], pr[MAXN];

struct fen {
	int st[MAXN];
	int que(int x){
		int te = 0;
		for(; x; x-=x&-x) te += st[x];
		return te;
	}
	void upd(int x, int p){
		for(; x<=MAXN-10; x+=x&-x) st[x] += p;
	}
} A;
signed main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>n;
	for(int i=1; i<=n; i++) cin>>a[i];
	int p; cin>>p;
	vector<int> cc; cc.pb(-INF);
	cc.pb(0);
	for(int i=1; i<=n; i++){
		a[i] -= p;
		pr[i] = pr[i-1]+a[i];
		cc.pb(pr[i]);
		// cout<< pr[i] << " i\n";
	}
	sort(cc.begin(), cc.end());
	cc.resize(unique(cc.begin(), cc.end()) - cc.begin());

	for(int i=0; i<=n; i++)
		pr[i] = lower_bound(cc.begin(), cc.end(), pr[i])-cc.begin();

	int ans = 0;
	A.upd(pr[0], 1);
	
	for(int i=1; i<=n; i++){ // bnyknya pref yg <= pr[i]
		ans += A.que(pr[i]);
		A.upd(pr[i], 1);
	}
	cout << ans << '\n';
}

• Subtask 1: 140 / 140