#include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>
#include <bitset>
#include <memory>
#include <chrono>
#define repeat(i,n) for (int i = 0; (i) < int(n); ++(i))
#define repeat_from(i,m,n) for (int i = (m); (i) < int(n); ++(i))
#define repeat_reverse(i,n) for (int i = (n)-1; (i) >= 0; --(i))
#define whole(f,x,...) ([&](decltype((x)) whole) { return (f)(begin(whole), end(whole), ## __VA_ARGS__); })(x)
using namespace std;
template <class T> void setmax(T & a, T const & b) { if (a < b) a = b; }
template <class T> void setmin(T & a, T const & b) { if (b < a) a = b; }
int main() {
    int n; cin >> n;
    vector<int> v(n), t(n); repeat (i,n) cin >> v[i] >> t[i];
    vector<int> ix(n);
    whole(iota, ix, 0);
    whole(sort, ix, [&](int i, int j) { return t[i] < t[j]; });
    int ans = -1;
    chrono::high_resolution_clock::time_point clock_begin = chrono::high_resolution_clock::now();
    while (true) {
        chrono::high_resolution_clock::time_point clock_end = chrono::high_resolution_clock::now();
        if (chrono::duration_cast<chrono::milliseconds>(clock_end - clock_begin).count() >= 4800) break;
        auto dp = make_unique<bitset<2*10000+1> >();
        (*dp)[0] = true;
        whole(random_shuffle, ix);
        for (int i : ix) {
            auto it = make_unique<bitset<2*10000+1> >();
            it->flip();
            *it <<= t[i];
            it->flip();
            *it &= *dp;
            *it <<= v[i];
            *dp |= *it;
        }
        repeat_reverse (i,dp->size()) {
            if ((*dp)[i]) setmax(ans, i);
            if (i == ans) break;
        }
    }
    cout << ans << endl;
    return 0;
}