1423. Maximum Points You Can Obtain from Cards

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Solution

Consider the left part and right part combination and find the max with the sliding window technique.

  public int maxScore(int[] cardPoints, int k) {
        int max = 0, score = 0, n = cardPoints.length;
        
        for(int i = 0; i < k; i++){
            score += cardPoints[i];
        }
        max = score;
        if( n == k ) return max;
        
        for(int i = 1; i <= k; i++){
            score += cardPoints[n-i] - cardPoints[k-i];
            max = Math.max(score, max);
        }
        return max;
    }