Submission #873866

#	Time	Username	Problem	Language	Result	Execution time	Memory
873866		noiaint	Star triangles (IZhO11_triangle)	C++17	100 / 100	229 ms	13872 KiB

triangle

#include <bits/stdc++.h>

using namespace std;

#define file ""

#define mp make_pair
#define fi first
#define se second
#define all(x) x.begin(), x.end()

#define getbit(x, i) (((x) >> (i)) & 1)
#define bit(x) (1LL << (x))
#define popcount __builtin_popcountll

mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r) {
    return l + rd() % (r - l + 1);
}

const int N = 1e6 + 5;
const int mod = (int)1e9 + 7; // 998244353;
const int lg = 25; // lg + 1
const int oo = 1e9;
const long long ooo = 1e18;

template<class X, class Y> bool mini(X &a, Y b) {
    return a > b ? (a = b, true) : false;
}
template<class X, class Y> bool maxi(X &a, Y b) {
    return a < b ? (a = b, true) : false;
}
void add(int &a, int b) {
    a += b;
    if (a >= mod) a -= mod;
    if (a < 0) a += mod;
}

int n;
vector<int> xa, ya;
vector<pair<int, int> > points;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    // freopen(file".inp", "r",stdin);
    // freopen(file".out", "w",stdout);

    cin >> n;
    for (int i = 0; i < n; ++i) {
    	int x, y;
    	cin >> x >> y;
    	xa.push_back(x);
    	ya.push_back(y);
    	points.emplace_back(x, y);
    }
    sort(all(xa));
    sort(all(ya));
    long long res = 0;
    for (auto [x, y] : points) {
    	int p = upper_bound(all(xa), x) - lower_bound(all(xa), x) - 1;
    	int q = upper_bound(all(ya), y) - lower_bound(all(ya), y) - 1;
    	res += 1LL * p * q;
    }
    cout << res;

    return 0;
}

/*

*/

• Subtask 1: 100 / 100