#include <bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i=0;i<n;++i)
#define rrep(i,n) for(int i=n-1;i>=0;i--)

int wa_greedy2(const int n, const vector<int> &A, const vector<int> &B) {
	int bb = accumulate(B.begin(), B.end(), 0);

	vector<tuple<double, int, int>> problems;
	rep(i, n) {
		problems.emplace_back(1.0 * A[i] / B[i], A[i], B[i]);
	}

	sort(problems.begin(), problems.end());

	int ans = bb;

	int aa = 0;
	rep(i, n) {
		aa += get<1>(problems[i]);
		bb -= get<2>(problems[i]);
		ans = min(ans, max(aa, bb));
	}
	return ans;
}

int main() {
	cin.tie(nullptr);
	ios::sync_with_stdio(false);

	int n;
	cin >> n;

	vector<int> A(n), B(n);
	rep(i, n) {
		cin >> A[i] >> B[i];
	}

	int ans = wa_greedy2(n, A, B);

	cout << ans << endl;

	return 0;
}