Submission #139713

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Source Code Expand

// include {{{
#include <cstdio>
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
//#include <deque>
#include <stack>
#include <queue>
//#include <map>
#include <set>
#include <algorithm>
#include <cmath>
#include <numeric>
//#include <complex>
// }}}
using namespace std;
// macro {{{
typedef long long ll;
typedef vector<int> vec;
typedef vector<vec> mat;
typedef pair<int,int> P;
#define rep(i,n) for(int i=0,__end=(n);i<__end;++i)
#define REP(i,j,k) for(int i=j,__end=(k);i<__end;++i)
//#define foreach(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();++it)
#define all(c) (c).begin(),(c).end()
#define rall(c) (c).rbegin(),(c).rend()
#define priority_queue_greater(T) priority_queue< T, vector<T>, greater<T> >
#define F first
#define S second
// }}}

int n;
int gcd(int n, int m){
  return m == 0 ? n : gcd(m, n%m);
}
ll rect(const P& a, const P& b){
  ll w = abs(a.F - b.F);
  ll h = abs(a.S - b.S);
  return w * h;
}
bool is_line(const P& a, const P& b, const P& c){
  int w1 = abs(a.F - b.F), h1 = abs(a.S - b.S);
  int w2 = abs(a.F - c.F), h2 = abs(a.S - c.S);
  int g1 = gcd(w1, h1), g2 = gcd(w2, h2);
  w1 /= g1; h1 /= g1;
  w2 /= g2; h2 /= g2;
  return w1 == w2 && h1 == h2;
}
int main(){
  while(cin >> n){
    vector<P> ps(n);
    rep(i,n){ scanf("%d%d", &ps[i].F, &ps[i].S); }

    int ans = 0;
    rep(i,n)REP(j,i+1,n)REP(k,j+1,n){
      P a = ps[i], b = ps[j], c = ps[k];
      if( is_line(a,b,c) ){ continue; }
      ll S = rect(a,b) + rect(b,c) + rect(c,a);
      if( S != 0 && S % 2 == 0 ){ ans++; }
    }
    cout << ans << endl;
  }
  return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:53:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]

Judge Result