1423. Maximum Points You Can Obtain from Cards.cpp

class Solution {
public:
    int maxScore(vector<int>& cardPoints, int k) {
        int n = cardPoints.size(), res = 0;
        for(int i =0 ; i<k;i++){
            res +=cardPoints[i];
        }
        int curr = res;
        for(int i = k-1;i>=0;i--){
           curr -=cardPoints[i];
            //[n-k+1] = last elemts of arr 
           curr += cardPoints[n-k+i];
           res = max(res,curr);
        }
        return res;
    }
};