#include <bits/stdc++.h>
#define entire(X) X.begin(),X.end()
#define LAMB [](point const &a, point const &b)->bool
#define LAMBI [&j](int const &a, int const &b)->bool
using namespace std; typedef long long ll;
void OJize(){cin.tie(NULL); ios_base::sync_with_stdio(false);}
struct point{
ll x, y;
point(ll x, ll y): x{x}, y{y} {}
};
ostream &operator<<(ostream &os, point const &p){
return os << p.x << ' ' << p.y;
}
// positive -> ccw; negative -> cw; 0 -> collinear
ll ccw(point a, point b, point c){
return (b.x-a.x)*(c.y-a.y) - (b.y-a.y)*(c.x-a.x);
}
int dp[2][3003][3003];
int prv[2][3003][3003];
vector<point> pnts;
int main(){OJize();
int n; cin>>n;
for(int i=0; i<n; i++){
ll x, y; cin>>x>>y;
pnts.push_back(point(x, y));
}
sort(entire(pnts), LAMB{return a.y < b.y;});
sort(pnts.begin()+1, pnts.end(), LAMB{return ccw(pnts[0], a, b) > 0;});
// base case
for(int i=1; i<n; i++) dp[0][0][i] = 2; // 0 = heel
// update
for(int j=1; j<n-1; j++){
vector<int> bef, aft;
for(int i=0; i<j; i++) bef.push_back(i);
for(int k=j+1; k<n; k++) aft.push_back(k);
sort(entire(bef), LAMBI{return ccw(pnts[j], pnts[a], pnts[b]) > 0;});
sort(entire(aft), LAMBI{return ccw(pnts[j], pnts[a], pnts[b]) > 0;});
int ptr = 0, maxd = 0, pid = 0;
for(int k: aft){
while(ptr<bef.size() && ccw(pnts[j], pnts[k], pnts[bef[ptr]]) > 0){
int i = bef[ptr++];
if(i && ccw(pnts[0], pnts[i], pnts[j]) == 0) continue;
if(dp[0][i][j] && maxd <= dp[0][i][j])
maxd = dp[0][i][j]+1, pid = i;
}
dp[1][j][k] = maxd, prv[1][j][k] = pid;
}
reverse(entire(bef)), reverse(entire(aft));
ptr = maxd = pid = 0;
for(int k: aft){
while(ptr<bef.size() && ccw(pnts[j], pnts[k], pnts[bef[ptr]]) < 0){
int i = bef[ptr++];
if(i && ccw(pnts[0], pnts[i], pnts[j]) == 0) continue;
if(dp[1][i][j] && maxd <= dp[1][i][j])
maxd = dp[1][i][j]+1, pid = i;
}
dp[0][j][k] = maxd, prv[0][j][k] = pid;
}
}
// answer
int ans = 0, ai = 0, aj = 0;
for(int i=1; i<n; i++) for(int j=i+1; j<n; j++){
if(ccw(pnts[i], pnts[j], pnts[0]) <= 0) continue;
if(ans < dp[0][i][j]) ans = dp[0][i][j], ai = i, aj = j;
}
if(ans == 0){cout << 0; return 0;}
vector<int> trace = {aj, ai};
while(trace.back()){
int sz = trace.size();
trace.push_back(prv[sz%2][trace[sz-1]][trace[sz-2]]);
}
reverse(entire(trace));
cout<<trace.size()<<'\n';
for(int x: trace) cout<<pnts[x]<<'\n';
}
