#include <iostream>
#include <climits>
#include <algorithm>
#include<vector>
#include<numeric>

using namespace std;

int main() {

	int d=0;
	int n;

	cin >> n;
	vector<int> a(n), b(n);
	for (int i = 0; i < n;i++)cin >> a[i] >> b[i];
	{
		int aa = 0;
		int bb = 0;
		for (int i = 0; i < n; i++) {
			if (a[i] < b[i])aa += a[i];
			else bb += b[i];
		}
		d = max(aa, bb);
	}//貪欲法
	int sumb = accumulate(b.begin(),b.end(),0);

	int dp[100][1000];
	for (int i = 0; i <= d; i++)dp[0][i] = 0;

	for (int i= 0; i < n; i++) {
		for (int j = 0; j <= d; j++) {
			if (j >= a[i])dp[i + 1][j] = max(dp[i][j - a[i]] + b[i], dp[i][j]);
			else dp[i + 1][j] = dp[i][j];
		}
	}
	int ans = d;
	for (int i = 0; i <= d;i++) {
		ans = min(ans, max(i, sumb - dp[n][i]));
	}

	cout << ans<<endl;

	return 0;
}