#include<bits/stdc++.h>
using namespace std;
long long arr[200200];
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n;
    long long sum = 0;
    cin >> n;
    for(int i = 0; i < n; i++){
        long long a, b;
        cin >> a >> b;
        arr[i] = 1ll * 2*a + b;
        sum += a;
    }
    sort(arr, arr+n, greater<long long>());
    for(int i = 0; i < n; i++){
        if(sum < 0){
            cout << i << '\n';
            return 0;
        }
        sum -= arr[i];
    }
    cout << n << '\n';
    return 0;
}
#include <stack>
#include <queue>
#include <bitset>
#include <unordered_set>
#include <unordered_map>
#include <map>
#include <set>
#include <tuple>
#include <cmath>
#include <random>
#include <algorithm>
#include <vector>
#include <iostream>
#include <fstream>
#include <chrono>
#include <numeric>

#define fio ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr)
#define rng mt19937_64 rnd(chrono::system_clock::now().time_since_epoch().count())

#define ri(...) i64 __VA_ARGS__; rx(__VA_ARGS__)
#define rc(...) char __VA_ARGS__; rx(__VA_ARGS__)
#define rs(...) string __VA_ARGS__; rx(__VA_ARGS__)
#define rvi(x, n) vi x(n); cin >> x
#define rvvi(x, n, m) vvi x(n, vi(m)); cin >> x

#ifndef ONLINE_JUDGE
#define dbg(...) cerr << '[' << #__VA_ARGS__ << "]: "; dbg_log(__VA_ARGS__)
#else
#define dbg(...) ;;
#endif

#define fa(i, v) for (auto &i : v)
#define fi(i, n) for (i32 i = 0; i < n; i++)
#define fp(i, n) for (i32 i = 1; i < n; i++)
#define fr(i, n) for (i32 i = n - 1; i >= 0; i--)
#define fu(i) ri(__i); fi(i, __i)

#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()

using namespace std;

typedef uint32_t u32;
typedef int32_t i32;
typedef uint64_t u64;
typedef int64_t i64;
#ifdef __SIZEOF_INT128__
typedef __uint128_t u128;
typedef __int128_t i128;
#endif
typedef vector<i64> vi;
typedef vector<vi> vvi;
typedef pair<i64, i64> pi;

template<typename T>
inline istream &operator>>(istream &in, vector<T> &v) {
    fa(x, v) in >> x;
    return in;
}

template<typename T>
inline ostream &operator<<(ostream &out, const vector<T> &v) {
    fa(x, v) out << x << ' ';
    return out;
}

template<typename T>
inline void rx(T &x) {
    cin >> x;
}

template<typename T, typename... R>
inline void rx(T &x, R &... l) {
    cin >> x;
    rx(l...);
}

template<typename T>
inline void dbg_log(const T &x) {
    cerr << x << endl;
}

template<typename T, typename... R>
inline void dbg_log(const T &x, const R &... l) {
    cerr << x << ", ";
    dbg_log(l...);
}

template<typename T>
inline void wl(const T &x) {
    cout << x << '\n';
}

template<typename T, typename... R>
inline void wl(const T &x, const R &... l) {
    cout << x << ' ';
    wl<R...>(l...);
}

int main() {
    fio;

    ri(n);
    vi qs(n);
    i64 fst = 0;
    fi(i, n) {
        ri(a, b);
        fst += a;
        qs[i] = 2 * a + b;
    }
    dbg(fst, qs);
    sort(rall(qs));
    i32 k = 0;
    while (fst >= 0) {
        fst -= qs[k++];
        dbg(k, fst);
    }
    wl(k);

    return 0;
}
