BOX

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define task "BOX"
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
const int mod = 998244353;
const int N = 1e5+5;
const int M = 5e3+5;
const ll base = 257;
const ll base1 = 311;
int n, m, ans, dp[M], k, lst[N];
bool trave[M*14][M];
vector<pii> adj[N];
struct box
{
    int c, w, id;
    bool operator < (const box& b)
    {
        return c+w < b.c+b.w;
    }
}b[N];
void sol(int itest)
{
    cin >> n;
    for(int i = 1; i <= n; i ++)
    {
        int c, w;
        cin >> c >> w;
        adj[w].pb({c, i});
    }
    for(int i = 1; i <= 5000; i ++)
    {
        sort(adj[i].begin(), adj[i].end());
        k = 5000/i+1;
        while(!adj[i].empty() && k > 0)
        {
            --k;
            ++m;
            b[m].c = adj[i].back().fi;
            b[m].id = adj[i].back().se;
            adj[i].pop_back();
            b[m].w = i;
        }
    }
    sort(b+1, b+1+m);
    fill_n(dp, M, -1);
    fill_n(lst, m+1, -1);
    dp[0] = 0;
    k = 0;
    for(int i = 1; i <= m; i ++)
    {
        for(int j = b[i].c; j >= 0; j --)
        {
            if(dp[j] == -1)continue;
            int nxt = min(5001, j+b[i].w);
            if(dp[nxt] < dp[j]+1)
            {
                if(nxt == 5001)lst[i] = j;
                else trave[i][nxt] = 1;
                dp[nxt] = dp[j]+1;
                if(ans < dp[nxt])
                {
                    ans = dp[nxt];
                    k = nxt;
                }
            }
        }
    }
    cout << ans << '\n';
    for(int i = m; i > 0; i --)
    {
        if(trave[i][k] && k <= 5000)
        {
            k -= b[i].w;
            cout << b[i].id <<(k == 0 ? "\n" : " ");
        }
        else if(lst[i] != -1 && k == 5001)
        {
            k  = lst[i];
            cout << b[i].id<<(k == 0 ? "\n" : " ");;
        }
    }
}
int main()
{
    if(fopen(task".inp", "r")){
       freopen(task".inp", "r", stdin);
       freopen(task".out", "w", stdout);
    }
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int ntest;
    ntest = 1;
    //cin >> ntest;
    for(int i = 1; i <= ntest; i ++)
        sol(i);
}