Submission #1078359

#	Time	Username	Problem	Language	Result	Execution time	Memory
1078359		vahagng	Star triangles (IZhO11_triangle)	C++17	100 / 100	371 ms	16064 KiB

triangle

//----------vahagng----------//
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
using namespace std;
// using namespace __gnu_pbds;

// template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif

void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}

#define ll long long
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define ld long double
#define sz(v) v.size()
#define endl '\n'

const ll inf = 1e18, mod = 1e9+7, mod1 = 998244353;

void SetIO(string str = "") {
    if (str != "") {
        freopen((str + ".in").c_str(), "r", stdin);
        freopen((str + ".out").c_str(), "w", stdout);
    } else {
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    }
}
 
void FastIO() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
}

ll mult(ll a, ll b){
    return (a*b)%mod;
}

ll add(ll a, ll b){
    return (a + b)%mod;
}

ll sub(ll a, ll b){
    return (a - b + mod)%mod;
}

/*
4 2 4
2 3
0 2
0 3
0 6
0 7
*/

// expected output
/*
2
3
1
*/

ll power(ll a, ll b){
    ll res = 1;
    while(b--){
        res *= a;
    }
    return res;
}

const int N = 3e5 + 10, M = N;

vector<pair<int,int>>v;
map<ll,ll> cx, cy;
ll n;

void solve(int tc){
    cin >> n;
    for(int i = 0; i < n; i++){
        int x, y;
        cin >> x >> y;
        cx[x]++, cy[y]++;
        v.push_back({x, y});
    }
    ll ans = 0;
    for(int i = 0; i < n; i++){
        auto [x, y] = v[i];
        cx[x]--, cy[y]--;
        ans += cx[x] * cy[y];
        cx[x]++, cy[y]++;
    }
    cout << ans << endl;
}

void precalc(){
}

int main() {
    // SetIO("");
    FastIO();
    int test_case = 1;
    // cin >> test_case;
    precalc();
    int cnt = 1;
    while (test_case--){
      solve(cnt++);
    }
    return 0;
}

Compilation message (stderr)

triangle.cpp: In function 'void SetIO(std::string)':
triangle.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen((str + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen((str + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:50:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   50 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100