解题：

#include<bits/stdc++.h>
using namespace std;
const int N=1e5+5;
long long a[N],b[N],pre1[N],pre2[N],suf1[N],suf2[N];
int main(){
    ios::sync_with_stdio(0),cin.tie(0);
    int n;cin>>n;
    for(int i=1;i<=n;++i)cin>>a[i];
    for(int i=1;i<=n;++i)cin>>b[i];
    for(int i=1;i<=n;++i){
        pre1[i]=max(pre1[i-1],0LL)+a[i]-b[i];
        pre2[i]=max(a[i]-b[i],pre2[i-1]+a[i]-2*b[i]);
    }
    for(int i=n;i>=1;--i){
        suf1[i]=max(suf1[i+1],0LL)+a[i]-b[i];
        suf2[i]=max(a[i]-b[i],suf2[i+1]+a[i]-2*b[i]);
    }
    for(int i=1;i<=n;++i){
        long long cross1=pre1[i]+suf2[i]-(a[i]-b[i]);
        long long cross2=pre2[i]+suf1[i]-(a[i]-b[i]);
        cout<<max({pre1[i],suf1[i],cross1,cross2})<<" ";
    }
    return 0;
    }

不喜勿说