Problem:
Score : 300 points

Problem Statement

There is a rectangle in a coordinate plane. The coordinates of the four vertices are (0,0), (W,0), (W,H), and (0,H).
You are given a point (x,y) which is within the rectangle or on its border. We will draw a straight line passing through (x,y) to cut the rectangle into two parts. Find the maximum possible area of the part whose area is not larger than that of the other. Additionally, determine if there are multiple ways to cut the rectangle and achieve that maximum.

Constraints

1 \leq W,H \leq 10^9

0\leq x\leq W

0\leq y\leq H

All values in input are integers.

Input

Input is given from Standard Input in the following format:

W H x y

Output

Print the maximum possible area of the part whose area is not larger than that of the other, followed by 1 if there are multiple ways to cut the rectangle and achieve that maximum, and 0 otherwise.

The area printed will be judged correct when its absolute or relative error is at most 10^{-9}.

Sample Input 1

2 3 1 2

Sample Output 1

3.000000 0

The line x=1 gives the optimal cut, and no other line does.

Sample Input 2

2 2 1 1

Sample Output 2

2.000000 1

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <iostream>
#include <algorithm>
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <complex>
#include <deque>
#include <valarray>
#include <unordered_map>
#include <unordered_set>
#include <array>
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <chrono>
#include <random>
#include <numeric>
using namespace std;
using ll = long long;
using ld = long double;
using str = string;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector<char> vc;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<vs> vvs;
typedef vector<vc> vvc;
typedef vector<vb> vvb;
using P = pair<ll,ll>;
#define REP(i, n) for (ll i = 0; i < (int)(n); i++)
#define RREP(i, n) for (ll i = (int)(n)-1; i > -1 ; i--)
#define IN(T, x) T x;cin >> x;
#define AIN(T, a, n) vector<T> a(n);REP(i, n){cin >> a[i];}
#define A2IN(T1, a, T2, b, n) vector<T1> a(n);vector<T2> b(n);REP(i, n){cin >> a[i] >> b[i];}
#define ALL(a) (a).begin(),(a).end()
#define SORT(a) sort(ALL(a))
#define RSORT(a) SORT(a);reverse(ALL(a))
#define pb push_back
#define mp make_pair
#define PF first
#define PS second
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return 1;}return 0;}
template<typename A, size_t N, typename T>void Fill(A (&array)[N], const T &val){fill( (T*)array, (T*)(array+N), val );}
#define OUT(x) cout << x << endl;
#define OUTD(x,n) cout << fixed << setprecision(n) << x << endl;
#define BOUT(b) if(b){OUT("Yes");}else{OUT("No");}
const ll MOD = 1000000007;
const ll INF = 10e9;
#define PI 3.14159265369;
ll dx[4] = {1,-1,0,0};
ll dy[4] = {0,0,1,-1};
ll ddx[8] = {1,1,1,-1,-1,-1,0,0};
ll ddy[8] = {0,1,-1,0,1,-1,1,-1};

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  
  IN(ll,W);
  IN(ll,H);
  IN(ll,x);
  IN(ll,y);
  cout << fixed << setprecision(10) << (ld)(W*H/2) << " ";
  if(W == x*2 && H == y*2){
    OUT(1);
  }else{
    OUT(0);
  }
}