#include using namespace std; #define INF 1000000007 #define LINF (1LL << 62) typedef long long i64; typedef pair P; inline i64 mod(i64 a, i64 m) { return (a % m + m) % m; } templatebool chmax(T &a, const T &b) { if (abool chmin(T &a, const T &b) { if (b> n; for(int i = 0; i < 2*n; i++){ cin >> a[i]; d[i+2] = d[i]+a[i]; } i64 ans = 0; for(int i = 0; i < n; i++){ chmax(ans, (d[2*n-i*2]+d[2*n+1]-d[2*n+1-i*2]) - (d[2*n+1-i*2]+d[2*n]-d[2*n-i*2])); } cout << ans << endl; } int main(){ std::cin.tie(0); std::ios::sync_with_stdio(false); int t = 1; //cin >> t; while(t--){ solve(); } return 0; }