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#include <bits/stdc++.h>
#define NMax 260
using namespace std;
ifstream fin ("gradina.in");
ofstream fout ("gradina.out");
struct DB
{
int x, y;
};
DB a[NMax];
int n, ans, ultimuly;
char sol[NMax];
int st[NMax], st2[NMax];
bool v[NMax];
int top, top2, N, M;
inline void Citire()
{
int i;
fin >> n;
for(i = 1; i <= n; i++)
fin >> a[i].x >> a[i].y;
}
inline bool Compar(const DB A, const DB B)
{
if(A.y == B.y)
return A.x < B.x;
return A.y < B.y;
}
///impart in doua semiplane
inline void Imparte()
{
int i, j;
sort(a + 1, a + n + 1, Compar);
for(j = 1; j <= n; j++)
{
ultimuly = a[j].y;
for(i = 1; i <= n; i++)
{
if(ultimuly <= a[i].y)
st[++N] = i;
else
st2[++M] = i;
}
}
}
///determinantul pentru determinarea semiplanului
double F(int i, int j, int p)
{
return a[p].x * (a[i].y - a[j].y) +
a[p].y * (a[j].x - a[i].x) +
a[i].x * a[j].y - a[j].x * a[i].y;
}
/// calculez aria celor doua poligoane
inline void Arie()
{
int i, arie = 0, arie2 = 0;
top++;
st[top] = st[1];
for(int i = 2; i <= top; i++)
arie += a[st[i - 1]].x * a[st[i]].y - a[st[i - 1]].y * a[st[i]].x;
top2++;
st2[top2] = st2[1];
for(int i = 2; i <= top2; i++)
arie2 += a[st2[i - 1]].x * a[st2[i]].y - a[st2[i - 1]].y * a[st[i]].x;
if(abs(arie - arie2) < ans)
{
ans = abs(arie - arie2);
for(i = 1; i <= N; i++)
sol[st[i]] = 'I';
for(i = 1; i <= M; i++)
sol[st2[i]] = 'I';
}
}
inline void Infasuratoare()
{
int i;
///planul de jos
st[1] = 1;
st[2] = 2;
top = 2;
for(i = 3; i <= N; i++)
{
while(top > 1 && F(st[top - 1], st[top], i) < 0)
{
v[st[top]] = 0;
top--;
}
st[++top] = i;
v[i] = 1;
}
for(i = N - 1; i >= 1; i--)
if(v[i] == 0)
{
while(F(st[top - 1], st[top], i) < 0)
{
v[st[top]] = 0;
top--;
}
st[++top] = i;
v[i] = 1;
}
///planul de sus
st2[1] = 1;
st2[2] = 2;
top2 = 2;
for(i = 3; i <= M; i++)
{
while(top > 1 && F(st2[top - 1], st2[top], i) < 0)
{
v[st2[top2]] = 0;
top2--;
}
st2[++top2] = i;
v[i] = 1;
}
for(i = M - 1; i >= 1; i--)
if(v[i] == 0)
{
while(F(st2[top2 - 1], st2[top2], i) < 0)
{
v[st2[top2]] = 0;
top2--;
}
st2[++top2] = i;
v[i] = 1;
}
for(i = 1; i <= M; i++)
if(v[i] == 0)
return;
Arie();
}
int main()
{
Citire();
Imparte();
return 0;
}