/* -*- coding: utf-8 -*-
 *
 * 710.cc: No.710 チーム戦 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 100;
const int MAX_A = 1000;
const int MAX_M = MAX_N * MAX_A;
const int INF = 1 << 30;

/* typedef */

/* global variables */

int as[MAX_N], bs[MAX_N];
int dp[MAX_M + 1];

/* subroutines */

inline void setmin(int &a, int b) { if (a > b) a = b; }
inline void setmax(int &a, int b) { if (a < b) a = b; }

/* main */

int main() {
  int n;
  scanf("%d", &n);

  int m = 0, bsum = 0;
  for (int i = 0; i < n; i++) {
    scanf("%d%d", &as[i], &bs[i]);
    m += min(as[i], bs[i]);
    bsum += bs[i];
  }

  fill(dp, dp + m + 1, -1);
  dp[0] = 0;
  
  for (int i = 0; i < n; i++) {
    int &ai = as[i], &bi = bs[i];
    for (int j = m - ai; j >= 0; j--)
      if (dp[j] >= 0) setmax(dp[j + ai], dp[j] + bi);
  }

  int mind = INF;
  for (int a = 0; a <= m; a++)
    setmin(mind, max(a, bsum - dp[a]));

  printf("%d\n", mind);
  return 0;
}