#include <cstdio>
#include <algorithm>
#include <numeric>
typedef long long ll;

const int MAXN = 2.5e4 + 10;

int n;
int a[MAXN], b[MAXN];
int order[MAXN];
ll ans = 0x7fffffffffffffff;

int main() {
  #ifdef LOCAL
    freopen("!input.in", "r", stdin);
    freopen("!output.out", "w", stdout);
  #else
    freopen("service.in", "r", stdin);
    freopen("service.out", "w", stdout);
  #endif

  scanf("%d", &n);
  for (int i = 1; i <= n; ++i) {
    scanf("%d %d", &a[i], &b[i]);
  }

  std::iota(order + 1, order + n + 1, 1);
  do {
    ll now = 0, waiting = 0;
    for (int i = 1; i <= n; ++i) {
      if ((now += a[order[i]]) >= ans) break;
      if (waiting <= now) {
        waiting = now + b[order[i]];
      } else if (waiting > now) {
        waiting += b[order[i]];
      }
    }
    ans = std::min(ans, std::max(now, waiting));
  } while (std::next_permutation(order + 1, order + n + 1));
  
  printf("%lld\n", ans);
  return 0;
}