from collections import defaultdict

INF = 1 << 30

n = int(input())
items = [tuple(map(int, input().split())) for _ in range(n)]

s = 0
dp = defaultdict(bool)
dp[0] = True
for i in range(n):
  ai, bi = items[i]
  s += ai
  ndp = defaultdict(bool)
  for x, _ in dp.items():
    ndp[x] = True
    ndp[x + bi - ai] = True

  dp = ndp

ans = s + min(list(dp.keys()))
print(ans)