#include <stdio.h>
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <map>
#include <iomanip>
#include <math.h> 
#include <stack>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <tuple>
#include <cctype>

using namespace std;
int n, a[100], b[100], minn = 99999999;

int func(int suma, int sumb, int cnt ) {

	if (cnt + 1 == n) {
		//cout << "suma->" << suma << " sumb->" << sumb << " cnt->" << cnt << endl;
		suma = max(suma, sumb);
		minn = min(minn, suma);

		return 0;
	}
	

	func(suma + a[cnt+ 1], sumb, cnt+1);
	func(suma, sumb + b[cnt + 1], cnt+1);





	return 0;
}

int main() {
	int i, j, k;
	

	cin >> n;

	for (i = 0; i < n; i++) {
		cin >> a[i] >> b[i];
	}


	func(a[0], 0, 0);
	func(0, b[0], 0);


	//cout << "minn->" << minn << endl;
	cout << minn << endl;










	getchar();
	getchar();
	return 0;
}