Calvins Game (Can Someone Tell Me What Am I Missing)


// https://www.codechef.com/INOIPRAC/problems/INOI1301
#include <bits/stdc++.h>
using namespace std;
#define ll long long

int main()
{
  ll n,k,tSum= -2000 ,tSum2=-2000,sumMax=-2000,eIndex=0;
  cin >> n >> k;
  ll arr[n],arrTemp[n],arrTemp2[n];
  eIndex = k-1;
  for(ll i=0;i<n;i++)
  {
    cin >> arr[i];
    arrTemp[i] = arr[i];
    arrTemp2[i] = arr[i];
  }
  for(ll i=k; i<n;i++)
  {
    if(i>k+1)
    {
      arrTemp[i] += max(arrTemp[i-1],arrTemp[i-2]);
    }
    else if(i == k+1)
    {
        arrTemp[i] += max(arrTemp[k],(ll) 0);
    }
    if(arrTemp[i] > tSum) //  think about equal to 
      {
        tSum = arrTemp[i];
        eIndex = i;
      }
  }
  // eIndex is where we are at right now and tSum has the current max sum
  for(ll i=eIndex-1; i >= 0;i--)
  {
    if(i < eIndex-2)
    {
      arrTemp2[i] += max(arrTemp2[i+1],arrTemp2[i+2]);
    }
    else if(i == eIndex-2)
    {
        arrTemp2[i] += max(arrTemp2[eIndex-1],(ll) 0);
    }
  }
  tSum2 = arrTemp2[0];

    for(ll i=k-2; i >= 0;i--)
  {
    if(i < k-3)
    {
      arr[i] += max(arr[i+1],arr[i+2]);
    }
    else if(i == k-3)
    {
        arr[i] += max(arr[k-2],(ll) 0);
    }
  }
  sumMax = arr[0];
  sumMax = max(tSum+tSum2,sumMax);
  if(k-1 == 0)
  {
    sumMax = max(sumMax,(ll) 0);
  }
  cout << sumMax;  
  return 0;
}

//The Code Failed On 6 Tasks Out Of 17, If Someone Can Take the Time To Go Through This

//And Explain What Am I Doing Wrong, I Will Be Very Thankful.