#include <bits/stdc++.h>
using namespace std;
int solve(vector<int> &A, int B) {
vector<int>pre(A.size()+1,0);
vector<int>suff(A.size()+1,0);
for(int i=1;i<=A.size();i++)
{
pre[i]=pre[i-1]+A[i-1];
// cout<<A[i-1]<<endl;
}
for(int i=1;i<=A.size();i++)
{
suff[i]=suff[i-1]+A[A.size()-i];
}
int maxi=0;
// for(int i=0;i<=A.size();i++)
// {
// cout<<pre[i]<<" ";
// }
// cout<<endl;
// for(int i=0;i<=A.size();i++)
// {
// cout<<suff[i]<<" ";
// }
for(int i=0;i<B;i++)
{
maxi=max(maxi,pre[i]+suff[B-i]);
}
return maxi;
}
int main() {
vector<int>A={5, -2, 3 , 1, 2 };
// cout<<A[A.size()-1]<<endl;
cout<<solve(A,3)<<endl;
}
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