Submission #671592

#	Time	Username	Problem	Language	Result	Execution time	Memory
671592		viwlesxq	Star triangles (IZhO11_triangle)	C++17	100 / 100	281 ms	13152 KiB

triangle

#include <bits/stdc++.h>
#include "ext/pb_ds/assoc_container.hpp"
#include "ext/pb_ds/tree_policy.hpp"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef string str;

#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
#define ordered_set tree<ll, null_type,less<ll>, rb_tree_tag,tree_order_statistics_node_update>
void freo(str x) {freopen((x + ".in").c_str(), "r", stdin);freopen((x + ".out").c_str(), "w", stdout);}
 
signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	int x[n], y[n];
	map <int, ll> mpx, mpy;
	for (int i = 0; i < n; i++) {
		cin >> x[i] >> y[i];
		mpx[x[i]]++;
		mpy[y[i]]++;
	}
	ll ans = 0;
	for (int i = 0; i < n; i++) {
		ans += (mpx[x[i]] - 1) * (mpy[y[i]] - 1);
	}
	cout << ans;
}

Compilation message (stderr)

triangle.cpp: In function 'void freo(str)':
triangle.cpp:21:26: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 | void freo(str x) {freopen((x + ".in").c_str(), "r", stdin);freopen((x + ".out").c_str(), "w", stdout);}
      |                   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:21:67: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 | void freo(str x) {freopen((x + ".in").c_str(), "r", stdin);freopen((x + ".out").c_str(), "w", stdout);}
      |                                                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100