Submission #357379

#	Time	Username	Problem	Language	Result	Execution time	Memory
357379		LastRonin	Star triangles (IZhO11_triangle)	C++11	100 / 100	825 ms	29124 KiB

triangle

#include <bits/stdc++.h>
#define pb push_back
#define ll long long
#define mp make_pair
#define si short int
#define speed ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#define pill pair<ll,ll>
#define f first
#define s second
#define pilc pair<ll,char>
#define all(a) (a).begin(),(a).end()
#define rep(s,e,step) for(int i = (s); i < (e) ; i += step)
#define vrep(s,e,step) for(int j = (s); j < (e) ; j += step)
#define ex exit(0) 
#define sz(a) (a).size()
#define triple pair<pill, ll>
#define pinode pair<node*, node*>
#define quadra pair<pill, pill>
#define ld long double
using namespace std;
 
const ll N = 4e5 + 10;
const ll M = 1e3 + 10;
const ll big = 1e9;
const ll hsh2 = 1964325029;
const ll wp = 491;
const long long mod = 1e9 + 7;
const long double EPS = 1e-14;
const ll block = 1e7;
const ll shift = 2e3;
mt19937_64 rofl(chrono::steady_clock::now().time_since_epoch().count());

ll n, x[N], y[N];

vector<ll> z, z2;

ll f[N], k[N];
map<pill, ll> cnt;
int main() {
	speed;
	cin >> n;
	for(int i = 1; i <= n; i++) {
		cin >> x[i] >> y[i];
		z.pb(x[i]), z2.pb(y[i]);
	}
	sort(all(z)), sort(all(z2));
	z.erase(unique(all(z)), z.end()), z2.erase(unique(all(z2)), z2.end());
	for(int i = 1; i <= n; i++) {
    	x[i] = lower_bound(all(z), x[i]) - z.begin();
    	y[i] = lower_bound(all(z2), y[i]) - z2.begin();
		f[x[i]]++;
		k[y[i]]++;
		cnt[mp(x[i], y[i])]++;		
    }
    ll ans = 0;
    for(int i = 1; i <= n; i++) {
    	ll b = cnt[mp(x[i], y[i])];
		ans += (f[x[i]] - b) * (k[y[i]] - b);
    }
    cout << ans;
}                     
/*
AAAACACA
*/

• Subtask 1: 100 / 100