#include <bits/stdc++.h>

using namespace std;
 
#define DEBUG(x) cerr<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cerr<<#v<<":";for(int i=0;i<v.size();i++) cerr<<" "<<v[i]; cerr<<endl;
#define DEBUG_MAT(v) cerr<<#v<<endl;for(int i=0;i<v.size();i++){for(int j=0;j<v[i].size();j++) {cerr<<v[i][j]<<" ";}cerr<<endl;}
typedef long long ll;
#define int ll
 
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
template<class S, class T> pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first + t.first, s.second + t.second); }
template<class S, class T> pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template<class S, class T> ostream& operator<<(ostream& os, pair<S, T> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
#define X first
#define Y second
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rep1(i,n) for(int i=1;i<=(int)(n);i++)
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define rrep1(i,n) for(int i=(int)(n);i>0;i--)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(),c.end()
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 (a>b) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl;
// int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
// int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {1, 0, -1, 0}, dy = {0, 1, 0, -1};
// vi dx2 = { 1,1,0,-1,-1,-1,0,1 }, dy2 = { 0,1,1,1,0,-1,-1,-1 };
#define fio() cin.tie(0); ios::sync_with_stdio(false);
const ll MOD = 1000000007;
// const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'

int dist(int x, int y, int nx, int ny) {
    return (x - nx) * (x - nx) + (y - ny) * (y - ny);
}

bool solve1(int n, vector<set<int>> x2y, map<pii, int> xy2i, vector<pii> xy) {
    vi num(n);
    priority_queue<pii, vector<pii>, greater<pii>> pq;

    rep (x, 501) {
        for (auto itr = x2y[x].begin(); itr != x2y[x].end(); itr++) {
            int y = *itr;
            for (int add = -9; add <= 9; add++) {
                int nx = x + add;
                if (not in(nx, 0, 501)) continue;
                auto itr = x2y[nx].lower_bound(y - 9);
                while (true) {
                    if (itr == x2y[nx].end()) break;
                    int ny = *itr;
                    if (dist(x, y, nx, ny) < 100) {
                        num[xy2i[pii(x, y)]]++;
                        itr++;
                    }
                    else {
                        if (ny <= y) itr++;
                        else break;
                    }
                }
            }
        }
    }
    // DEBUG_VEC(num);

    vector<bool> used(n);
    rep (i, n) pq.push(pii(num[i], i));

    int k = 0;
    vi ans;
    while (k * 90 < n) {
        if (pq.size() == 0) return false;
        pii temp = pq.top();
        pq.pop();
        if (used[temp.second]) continue;
        int x = xy[temp.second].first, y = xy[temp.second].second;
        if (x2y[x].count(y) == 0) continue;
        used[temp.second] = true;
        k++;
        ans.push_back(temp.second);

        vector<pii> era_xy;
        for (int add = -9; add <= 9; add++) {
            int nx = x + add;
            if (not in(nx, 0, 501)) continue;
            auto itr = x2y[nx].lower_bound(y - 9);
            while (true) {
                if (itr == x2y[nx].end()) break;
                int ny = *itr;
                if (dist(x, y, nx, ny) < 100) {
                    x2y[nx].erase(itr);
                    itr = x2y[nx].lower_bound(ny);
                    era_xy.push_back(pii(nx, ny));
                }
                else {
                    if (ny <= y) itr++;
                    else break;
                }
            }
        }

        set<pii> xxyy;
        rep (i, era_xy.size()) {
            int x = era_xy[i].first, y = era_xy[i].second;
            for (int add = -9; add <= 9; add++) {
                int nx = x + add;
                if (not in(nx, 0, 501)) continue;
                auto itr = x2y[nx].lower_bound(y - 9);
                while (true) {
                    if (itr == x2y[nx].end()) break;
                    int ny = *itr;
                    if (dist(x, y, nx, ny) < 100) {
                        num[xy2i[pii(nx, ny)]]--;
                        xxyy.insert(pii(nx, ny));
                        itr++;
                    }
                    else {
                        if (ny <= y) itr++;
                        else break;
                    }
                }
            }
        }

        for (auto itr = xxyy.begin(); itr != xxyy.end(); itr++) {
            int x = itr->first, y = itr->second;
            int idx = xy2i[pii(x, y)];
            pq.push(pii(num[idx], idx));
        }
    }
    // rep (i, ans.size()) {
    //     for (int j = i + 1; j < ans.size(); j++) {
    //         if (dist(xy[ans[i]].first, xy[ans[i]].second, xy[ans[j]].first, xy[ans[j]].second) < 100) assert(false);
    //     }
    // }
    cout << k << endl;
    rep (i, ans.size()) cout << ans[i] + 1 << " ";
    cout << endl;
    return true;
}

bool solve2(int n, vector<set<int>> x2y, map<pii, int> xy2i, vector<pii> xy, bool x_flip, bool y_flip, bool rotate) {
    rep (x, 501) {
        for (auto itr = x2y[x].begin(); itr != x2y[x].end(); itr++) {
            int y = *itr;
            for (int add = -9; add <= 9; add++) {
                int nx = x + add;
                if (not in(nx, 0, 501)) continue;
                auto itr = x2y[nx].lower_bound(y - 9);
                while (true) {
                    if (itr == x2y[nx].end()) break;
                    int ny = *itr;
                    if (dist(x, y, nx, ny) < 100) {
                        itr++;
                    }
                    else {
                        if (ny <= y) itr++;
                        else break;
                    }
                }
            }
        }
    }
    // DEBUG_VEC(num);

    priority_queue<pii, vector<pii>, greater<pii>> pq;
    vector<bool> used(n);
    rep (i, n) {
        pii temp = xy[i];
        if (x_flip) temp.first *= -1;
        if (y_flip) temp.second *= -1;
        if (rotate) {
            pii ntemp;
            ntemp.first = temp.first + temp.second;
            ntemp.second = temp.first - temp.second;
            temp = ntemp;
        }
        pq.push(temp);
    }

    int k = 0;
    vi ans;
    while (k * 90 < n) {        
        if (pq.size() == 0) return false;
        pii xy = pq.top();
        pq.pop();
        if (rotate) {
            pii temp;
            temp.first = (xy.first + xy.second) / 2;
            temp.second = (xy.first - xy.second) / 2;
            xy = temp;
        }
        if (x_flip) xy.first *= -1;
        if (y_flip) xy.second *= -1;
        int idx = xy2i[xy];
        if (used[idx]) continue;
        int x = xy.first, y = xy.second;
        if (x2y[x].count(y) == 0) continue;

        used[idx] = true;
        k++;
        ans.push_back(idx);

        vector<pii> era_xy;
        for (int add = -9; add <= 9; add++) {
            int nx = x + add;
            if (not in(nx, 0, 501)) continue;
            auto itr = x2y[nx].lower_bound(y - 9);
            while (true) {
                if (itr == x2y[nx].end()) break;
                int ny = *itr;
                if (dist(x, y, nx, ny) < 100) {
                    x2y[nx].erase(itr);
                    itr = x2y[nx].lower_bound(ny);
                    era_xy.push_back(pii(nx, ny));
                }
                else {
                    if (ny <= y) itr++;
                    else break;
                }
            }
        }
    }
    cout << k << endl;
    rep (i, ans.size()) cout << ans[i] + 1 << " ";
    cout << endl;
    return true;
}

signed main() {
    fio();
    int n;
    cin >> n;
    vector<set<int>> x2y(501);
    map<pii, int> xy2i;
    vector<pii> xy;

    rep (i, n) {
        int x, y;
        cin >> x >> y;
        x2y[x].insert(y);
        xy2i[pii(x, y)] = i;
        xy.push_back(pii(x, y));
    }

    
    rep (i, 2) {
        rep (j, 2) {
            rep (k, 2) {
                if (solve2(n, x2y, xy2i, xy, i, j, k)) return 0;
            }
        }
    }
    // if (solve1(n, x2y, xy2i, xy)) return 0;
}