import numpy as np

N = int(input())
MAX = 20000

homes = [tuple(map(int, input().split())) for _ in range(N)]
homes.sort(key=lambda x: x[0] + x[1])

dp = np.zeros(MAX + 1, dtype=bool)
dp[0] = True
for v, t in homes:
    new_dp = dp.copy()
    new_dp[v:v + t] |= dp[:t]
    dp = new_dp

print(np.nonzero(dp)[0].max())