Submission #1564022

---

Source Code Expand

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

typedef int _loop_int;
#define REP(i,n) for(_loop_int i=0;i<(_loop_int)(n);++i)
#define FOR(i,a,b) for(_loop_int i=(_loop_int)(a);i<(_loop_int)(b);++i)
#define FORR(i,a,b) for(_loop_int i=(_loop_int)(b)-1;i>=(_loop_int)(a);--i)

#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define DEBUG_VEC(v) cout<<#v<<":";REP(i,v.size())cout<<" "<<v[i];cout<<endl
#define ALL(a) (a).begin(),(a).end()

#define CHMIN(a,b) a=min((a),(b))
#define CHMAX(a,b) a=max((a),(b))

// mod
const ll MOD = 998244353ll;
#define FIX(a) ((a)%MOD+MOD)%MOD

// floating
typedef double Real;
const Real EPS = 1e-11;
#define EQ0(x) (abs(x)<EPS)
#define EQ(a,b) (abs(a-b)<EPS)
typedef complex<Real> P;

int n;
pii pts[252];
ll bin[252];

int cross(pii a,pii b){
  return a.first*b.second - a.second*b.first;
}
int sp(pii a,pii b,pii c){
  pii x = pii(b.first-a.first, b.second-a.second);
  pii y = pii(c.first-a.first, c.second-a.second);
  return cross(x,y);
}

int main(){
  scanf("%d",&n);
  REP(i,n){
    int x,y;
    scanf("%d%d",&x,&y);
    pts[i] = pii(x,y);
  }

  bin[0] = 1;
  FOR(i,1,252)bin[i] = bin[i-1]*2%MOD;

  ll ans = bin[n];
  FOR(i,0,n)FOR(j,i+1,n){
    int x = 0;
    FOR(k,j+1,n){
      if(sp(pts[i],pts[j],pts[k]) == 0){
        x++;
      }
    }
    ans -= bin[x];
  }
  ans -= n;
  ans -= 1;
  printf("%lld\n",FIX(ans));
  return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:48:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d",&n);
                 ^
./Main.cpp:51:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&x,&y);
                        ^

Judge Result