Submission #46965

#	Time	Username	Problem	Language	Result	Execution time	Memory
46965		robert	Star triangles (IZhO11_triangle)	C++14	100 / 100	568 ms	38900 KiB

triangle

#include <cstdio>
#include <map>

using namespace std;

int main(){
	int N; scanf("%d", &N);
	int x[300100], y[300100];
	map<int, int> ctx, cty;
	for(int n=0; n<N; n++){
		scanf("%d %d", &x[n], &y[n]);
		ctx[x[n]]++;
		cty[y[n]]++;
	}
	long long ans = 0;
	for(int n=0; n<N; n++){
		ans += (ctx[x[n]]-1)*(cty[y[n]]-1);
	}
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

triangle.cpp: In function 'int main()':
triangle.cpp:7:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int N; scanf("%d", &N);
         ~~~~~^~~~~~~~~~
triangle.cpp:11:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &x[n], &y[n]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100