Submission #171351

#	Time	Username	Problem	Language	Result	Execution time	Memory
171351		ASDF123	Star triangles (IZhO11_triangle)	C++14	100 / 100	639 ms	13316 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
#define all(s) s.begin(), s.end()	
#define szof(s) (int)s.size()
#define pii pair<int, int>
#define prev myyyyrza1
#define pb push_back
#define y1 myyyyrza2
#define id id1234
#define fr first
#define sc second
#define OK() puts("OK")
using namespace std;
 
const int N = ((int)3e5 + 5);
const int MOD = (1e9 + 7);
const int INF = (0x3f3f3f3f);

int X[N], Y[N];

map <int, long long> cntx, cnty;

main() {
	int n;
	cin >> n;
	for (int i = 1; i <= n; i++) {
		scanf("%d%d", &X[i], &Y[i]);
		cnty[Y[i]]++;
		cntx[X[i]]++;
	}
	
	long long ans = 0;
	for (int i = 1; i <= n; i++) {
		int x = X[i], y = Y[i];
		ans += (cntx[x] - 1) * (cnty[y] - 1);
	}
	cout << ans;
}

Compilation message (stderr)

triangle.cpp:23:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
triangle.cpp: In function 'int main()':
triangle.cpp:27:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &X[i], &Y[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100