Maximum_subarray_sum.cpp

// There is an integer array of N heights. You have to pick certain number of heights
// from the array everytime. Find the maximum  sum of all the heights picked 
// everytime that meet the following conditions:
//     - The length of the subarray is L, and
//     - All the heights of the subarray picked are distinct.

// Return the maximum subarray sum of all the height subarrays that meet the 
// conditions. If no heights subarray meets the conditions, return 0.

// - A subarray is a contiguous non-empty sequence of elements within an array.

// Input Format:
// -------------
// Line-1: Two space separated integers, N and L
// Line-2: N space separated integers, height[].

// Output Format:
// --------------
// Print an integer result.


// Sample Input-1:
// ---------------
// 7 3
// 7 7 7 1 5 4 2

// Sample Output-1:
// ----------------
// 13

// Explanation: 
// ------------
// The subarrays of length 3 of height array are:
//     - [7,7,7] this subarray does not meet the requirement because the 7 is repeated.
//     - [7,7,1] this subarray does not meet the requirement because the 7 is repeated.
//     - [7,1,5] this subarray meets the requirements and its sum is 13.
//     - [1,5,4] this subarray meets the requirements and its sum is 10.
//     - [5,4,2] this subarray meets the requirements and its sum is 11. 

// Return 13 because it is the maximum subarray sum of all the subarrays 
// that meet the conditions


// Sample Input-2:
// ---------------
// 3 3
// 7 7 7

// Sample Output-2:
// ----------------
// 0

// Explanation:
// ------------
// The subarrays of length 3 of height array are:
// - [7,7,7] which does not meet the requirements because the element 7 is repeated.

// Return 0 because no subarrays meet the conditions.





#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,k;
    cin>>n>>k;
    vector<int> v(n,0);
    for(int i=0;i<n;i++){
        cin>>v[i];
    }
    int maxi=0;
    for(int i=0;i<n-k+1;i++){
        unordered_map<int,int> m;
        int s=0;
        for(int j=i;j<i+k;j++){
            s=s+v[j];
            m[v[j]]=m[v[j]]+1;
        }
        if(m.size()==k){
            maxi=max(maxi,s);
        }
        else{
            continue;
        }
    }
    cout<<maxi;
}