#include <bits/stdc++.h>
#define val first
#define pos second
using namespace std ;
const int NR = 100005 ;
int64_t a [ NR ] , b [ NR ] , n ;
pair < int64_t , int64_t > sol [ NR ] ;
int main () {
    int64_t i , j , ans = 0 ;
   cin >> n ;
   for ( i = 1 ; i <= n ; ++ i )    {
    cin >> a [ i ] ;
    a [ i ] += a [ i - 1 ] ;
   }
   for ( i = 1 ; i <= n ; ++ i )    {
    cin >> b [ i ] ;
    b [ i ] += b [ i - 1 ] ;
    sol [ i ].val = b [ i ] - a [ i ] ;
    sol [ i ].pos = i ;
   }

    sort ( sol , sol + n + 1 ) ;
    for ( i = 0 ; i <= n ; ++ i )   {
        for ( j = i ; j <= n && sol [ i ].val == sol [ j ].val ; j ++ ) ;
        j -- ;
        ans = max ( ans , sol [ j ].pos - sol [ i ].pos ) ;
        i = j ;
    }
    cout << ans ;
}