#include<iostream>
#include<algorithm>
#include<vector>
#include<queue>
using namespace std;
int n;
struct node {
    int a, b;
    bool operator<(node& c) {
       return  b < c.b;
    }
}a[150005];
priority_queue<int> q;
int main()
{
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i].a >> a[i].b;
    }
    sort(a + 1, a + n + 1);
    long long sum = 0;
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        sum += a[i].a;
        q.push(a[i].a);
        if (sum <= a[i].b) {
            ans++;
        }
        else {
            sum -= q.top();
            q.pop();
        }
    }
    cout << ans;
}