# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
142547 | 2019-08-09T14:01:26 Z | vardan__02 | Star triangles (IZhO11_triangle) | C++14 | 0 ms | 0 KB |
#include <iostream> #include <algorithm> #include <cmath> #include <vector> #include <queue> #include <deque> #include <cstring> #include <string> #include <set> #define ll long long #define ld long double using namespace std; map<ll,ll> x,y; ll i, j, n, m, k, p, q, a[300005], b[300005]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n; for (i = 1; i <= n; i++) { cin >> a[i] >> b[i]; x[a[i]]++; y[b[i]]++; } for (i = 1; i <= n; i++) m += (x[a[i]] - 1)*(y[b[i]] - 1); cout << m << endl; return 0; }