Submission #1150258

#	Time	Username	Problem	Language	Result	Execution time	Memory
1150258		AgentPengin	Star triangles (IZhO11_triangle)	C++20	100 / 100	407 ms	12748 KiB

triangle

/**
 *    author:  AgentPengin ( Độc cô cầu bại )
 *    created: 23.12.2022 10:08:02
 *    too lazy to update time
**/
#include<bits/stdc++.h>

#define EL '\n'
#define fi first
#define se second
#define NAME "TASK"
#define ll long long
#define lcm(a,b) (a/gcd(a,b))*b
#define db(val) "["#val" = " << (val) << "] "
#define bend(v) (v).begin(),(v).end()
#define sz(v) (int)(v).size()
#define ex exit(0)
#define int ll

using namespace std;

const ll mod = 1e9 + 7;
const int inf = 0x1FFFFFFF;
const int MAXN = 1e5 + 5;

int n;
map<int,int> mp_x,mp_y;
vector<pair<int,int>> point;

signed main() {
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    if (ifstream(NAME".inp")) {
        freopen(NAME".inp","r",stdin);
        freopen(NAME".out","w",stdout);
    }
    cin >> n;
    for (int i = 1;i <= n;i++) {
    	int x,y; cin >> x >> y;
    	mp_x[x]++;
    	mp_y[y]++;
    	point.push_back(make_pair(x,y));
    }
    int ans = 0;
    for (auto x : point) {
    	ans += (mp_x[x.fi] - 1) * (mp_y[x.se] - 1);
    }
    cout << ans;
    
    
    cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
    return 0;
}
// agent pengin wants to take apio (with anya-san)

Compilation message (stderr)

triangle.cpp: In function 'int main()':
triangle.cpp:33:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |         freopen(NAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:34:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         freopen(NAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100