Submission #1582747

---

Source Code Expand

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

#define int long long

#define rep(i,n) for(int i=0;i<(n);i++)
#define pb push_back
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
typedef vector<int>vint;
typedef pair<int,int>pint;
typedef vector<pint>vpint;

template<typename A,typename B>inline void chmin(A &a,B b){if(a>b)a=b;}
template<typename A,typename B>inline void chmax(A &a,B b){if(a<b)a=b;}

const int mod=998244353;

int N;
vpint P;

int po[222];

signed main(){
    po[0]=1;
    for(int i=1;i<222;i++)po[i]=po[i-1]*2%mod;
    cin>>N;
    rep(i,N){
        int x,y;
        cin>>x>>y;
        P.pb({x,y});
    }
    sort(all(P));

    int ans=po[N];
    ans=(ans-1+mod)%mod;
    ans=(ans-N+mod)%mod;
    for(int i=0;i<N;i++){
        for(int j=i+1;j<N;j++){
            int dx=P[j].fi-P[i].fi;
            int dy=P[j].se-P[i].se;

            int cnt=0;
            for(int k=j+1;k<N;k++){
                int dxx=P[k].fi-P[i].fi;
                int dyy=P[k].se-P[i].se;

                if(dy*dxx!=dx*dyy)continue;
                cnt++;
            }
            ans=(ans-po[cnt]+mod)%mod;
        }
    }
    cout<<ans<<endl;
    return 0;
}

Submission Info

Judge Result