n = int(input())
A = []
B = []

for i in range(n):
    a,b = map(int,input().split())
    A.append(a)
    B.append(b)

a=b=sum_b=0

for i in range(n):
    if a<b:
        a += A[i]
    else:
        b += B[i]
    sum_b += B[i]

ma = max(a,b)
dp = [0]*ma

for i in range(n):
    a = A[i]
    b = B[i]
    for j in range(ma-a-1,-1,-1):
        dp[j+a] = max(dp[j+a],dp[j]+b)
        
ans = ma

for i in range(ma):
    ans = min(ans,max(i,sum_b-dp[i]))
    if i>ans:
        break

print(ans)