I found out the max sum subarray. The elements included in this list should be added to Ans (I am assuming that we placed '(' one element before the maxsumsubarray started, and we placed ')' after the last element of maxsumsubarray) Now subtract the elements which weren't included in this subarray, except the first element of the vector, which has to be added.

This doesn't work for sample test case 4: [{-11,-4,28,38,21,-29,-45,11,-58,-39,92,35,-56,-6,29,-2,61,10,-29,-63},{19,5,3,10,4,18,5,2,0,15},{-19,21,7,-66,38,-39,-22,24,-32,13}]

Can anyone explain why? Moreover, what is the correct way to solve this question?

#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>

using namespace std;
vector<int> poss;
vector<int> pose;
int myposs,mypose;

int maxsum(vector<int> a)
{
    int i,n=(int)a.size(),sc;
    vector<int> S(a.begin(),a.end());
    poss.clear();
    pose.clear();
    
    for(i=0;i<n;i++)
    {
        poss.push_back(i);
        pose.push_back(i);
    }
    for(i=3;i<n;i++)
    {
        if(S[i]<S[i-1]+S[i])
        {
            S[i]=S[i-1]+S[i];
            poss[i]=poss[i-1];
        }
    }
    
    int m=INT_MIN;
    for(i=2;i<n;i++)
    {
        if(S[i]>m)
        {
            myposs=poss[i];
            mypose=pose[i];
            m = S[i];
        }
    }
    
    int j;
    
    if(!(myposs==0 && mypose==n-1))
    {
        if(myposs!=0)
            m=m+a[0];
        
        for(j=1;j<myposs;j++)
            m=m-a[j];
        
        for(j=mypose+1;j<n;j++)
            m=m-a[j];
        
    }

    
    int s = 0;
    
    for(i=0;i<n;i++)
    {
        if(i==0)
            s=s+a[i];
        else
            s = s-a[i];
    }
    
    if(s>m)
    {
        myposs=0;
        mypose=n-1;
        return s;
    }
    
    else
        return m;
}
class SuccessiveSubtraction2 {
public:
    vector <int> calc(vector <int> a, vector <int> p, vector <int> v) {
        
        int i,s,j,n=(int)a.size();
        vector<int> ans;
        
        for(i=0;i<(int)p.size();i++)
        {
            a[p[i]]=v[i];
            s=0;

            s = maxsum(a);
            
            ans.push_back(s);
        }
        
        return ans;
        
    }
};

http://community.topcoder.com/stat?c=problem_statement&pm=13699&rd=16318