n = int(input())
M = 1<<30
dp = [0]
for _ in range(n):
    a,b = map(int,input().split())
    bmax = M
    ndp = []
    for x in dp:
        if x%M >= bmax: continue
        bmax = x%M
        ndp.append(x+a*M)
        ndp.append(x+b)
    dp = ndp
    dp.sort()

print(min(max(divmod(x,M)) for x in dp))