#include <iostream>
#include <iomanip>
#include <vector>
#include <map>
#include <string>
#include <cstring>
#include <set>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cmath>

using namespace std;

struct line
{
    int x, y, num;
};

bool comp (line a, line b)
{
    if (a.x == b.x)
        return a.y < b.y;

    return a.x < b.x;
}

vector <line> lines;
int d[500], c[500];

int f (int v)
{
    if (d[v])
        return d[v];

    int i = v + 1, t, mx = 0;

    while (i < lines.size() && lines[i].x == lines[v].x)
        i++;

    if (i == lines.size())
        return d[v] = 1;

    while (i < lines.size() && lines[i].y < lines[v].y)
    {
        t = f(i);

        if (t > mx)
        {
            mx = t;
            c[v] = i;
        }

        i++;
    }

    return d[v] = mx + 1;
}

int main()
{
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);

    int n, i, j, a, b, mx = 1, mi = 0;
    vector <int> ans;
    line tl;

    cin >> n;

    for (i = 0; i < n; i++)
    {
        cin >> a >> b;

        tl.num = i + 1;
        tl.x = a;
        tl.y = b;

        lines.push_back(tl);

        c[i] = -1;
    }

    sort(lines.begin(), lines.end(), comp);

    for (i = 0; i < lines.size(); i++)
        if (f(i) > mx)
        {
            mx = d[i];
            mi = i;
        }

    while (mi != -1)
    {
        ans.push_back(mi);
        mi = c[mi];
    }

    cout << ans.size() << endl;

    reverse(ans.begin(), ans.end());

    for (i = 0; i < ans.size(); i++)
        cout << lines[ans[i]].num << ' ';

    return 0;
}