Submission #1752171

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

const int N = 205;
const int mod = 998244353;

int n, res = 1;
int x[N], y[N];

int main() {
	ios::sync_with_stdio(false);
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> x[i] >> y[i]; res = 2 * res % mod; 
	}
	res = (res - 1 + mod) % mod;
	res = (res - n + mod) % mod;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < i; ++j) {
			int sub = 1;
			for (int k = 0; k < j; ++k) {
				if ((y[j] - y[i]) * (x[k] - x[j]) == (x[j] - x[i]) * (y[k] - y[j])) sub = 2 * sub % mod;
			}
			res = (res - sub + mod) % mod;
		}
	}
	cout << res;
}

Submission Info

Judge Result