BOJ 6165 Game of Lines

#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <cstring>
#include <string>
#include <algorithm>
#include <cmath>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
typedef long long int ll;
using namespace std;
#define INF 1234567890
#define LIMIT 1
int n, m;
int x[205], y[205];
set<double> sset;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);

	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> x[i] >> y[i];
	}
	bool isZero = false;
	for (int i = 0; i < n; i++) {
		for (int j = i + 1; j < n; j++) {
			int dx, dy;
			double dydx;
			dx = x[i] - x[j];
			dy = y[i] - y[j];
			if (dx == 0) {
				isZero = true;
			}
			else {
				dydx = (double)dy / dx;
				sset.insert(dydx);
			}
			
		}
	}
	
	int ans = sset.size();
	if (isZero)
		ans++;
	cout << ans;

	return 0;
}

Game of Lines

시간 제한	메모리 제한	제출	정답	맞은 사람	정답 비율
1 초	128 MB	77	36	32	47.761%

문제

Farmer John has challenged Bessie to the following game: FJ has a board with dots marked at N (2 <= N <= 200) distinct lattice points. Dot i has the integer coordinates X_i and Y_i (-1,000 <= X_i <= 1,000; -1,000 <= Y_i <= 1,000).

Bessie can score a point in the game by picking two of the dots and drawing a straight line between them; however, she is not allowed to draw a line if she has already drawn another line that is parallel to that line. Bessie would like to know her chances of winning, so she has asked you to help find the maximum score she can obtain.