Submission #341713

#	Time	Username	Problem	Language	Result	Execution time	Memory
341713		spike1236	Star triangles (IZhO11_triangle)	C++14	0 / 100	3 ms	364 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define f first
#define s second
#define ll long long
#define ld long double
#define all(_v) _v.begin(), _v.end()
#define sz(_v) (int)_v.size()
#define pii pair <int, int>
#define pll pair <ll, ll>
#define veci vector <int>
#define vecll vector <ll>

const int dx[4] = {1, -1, 0, 0};
const int dy[4] = {0, 0, -1, 1};
const double PI = 3.1415926535897932384626433832795;
const double eps = 1e-9;
const int MOD1 = 1e9 + 7;
const int MOD2 = 998244353;

const int MAXN = 3e5 + 10;
pii a[MAXN];
map <int, veci> x, y;


void solve() {
    int n;
    cin >> n;
    for(int i = 1; i <= n; ++i) {
        cin >> a[i].f >> a[i].s;
        x[a[i].f].pb(a[i].s);
        y[a[i].s].pb(a[i].f);
    }
    ll ans = 0;
    for(int i = 1; i <= n; ++i) {
        ll res1, res2;
        res1 = res2 = 0;
        if(x[a[i].f].back() > a[i].s) res1 = x[a[i].f].end() - upper_bound(all(x[a[i].f]), a[i].s);
        if(y[a[i].s].back() > a[i].f) res2 = y[a[i].s].end() - upper_bound(all(y[a[i].s]), a[i].f);
        ans += res1 * 1ll * res2;
        res2 = 0;
        if(y[a[i].s][0] < a[i].f) res2 = lower_bound(all(y[a[i].s]), a[i].f) - y[a[i].s].begin();
        ans += res1 * 1ll * res2;
        res1 = 0;
        if(x[a[i].f][0] < a[i].s) res1 = lower_bound(all(x[a[i].f]), a[i].s) - x[a[i].f].begin();
        ans += res1 * 1ll * res2;
        res2 = 0;
        if(y[a[i].s].back() > a[i].f) res2 = y[a[i].s].end() - upper_bound(all(y[a[i].s]), a[i].f);
        ans += res1 * 1ll * res2;
    }
    cout << ans;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    freopen("triangles.in", "r", stdin);
    freopen("triangles.out", "w", stdout);
    int T = 1;
    ///cin >> T;
    while(T--) solve(), cout << '\n';
    return 0;
}

Compilation message (stderr)

triangle.cpp: In function 'int main()':
triangle.cpp:60:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   60 |     freopen("triangles.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:61:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   61 |     freopen("triangles.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 100