Amazon OA Experience | 1st week January | SDE-2

Round 1

Questions:

1. The first problem was similar to this post: Amazon OA Question - Parentheses Perfection Kit.

   Solution for the 1st problem:

   public static long findMaxEfficiencyScore(String s, String kitParentheses, List<Integer> efficiencyRatings) {
       // Write your code here
       //open & close ratings score separate and sort desc
       //see already balanced or make balanced somehow using open & close
       //then try to achieve more score using open & close both at a time after balance.
       int n = efficiencyRatings.size();
       List<Integer> open = new ArrayList<>();
       List<Integer> close = new ArrayList<>();
       for(int i = 0; i < kitParentheses.length(); i++) {
           if(kitParentheses.charAt(i) == '(') {
               open.add(efficiencyRatings.get(i));
           }
           else {
               close.add(efficiencyRatings.get(i));
           }
       }
       Collections.sort(open, Collections.reverseOrder());
       Collections.sort(close, Collections.reverseOrder());
       Stack<Character> stack = new Stack<>();
       int closingBracket = 0;
       for(int i = 0; i < s.length(); i++) {
           if(s.charAt(i) == '(') {
               stack.push(s.charAt(i));
           }
           else if(!stack.isEmpty()) {
               stack.pop();
           }
           else {
               closingBracket++;
           }
       }
       int openBracket = stack.size();
       long score = 0;
       int indexClose = 0;
       while(openBracket > 0) {
           score += close.get(indexClose++);
           openBracket--;
       }
       int indexOpen = 0;
       while(closingBracket > 0) {
           score += open.get(indexOpen++);
           closingBracket--;
       }
       while(indexOpen < open.size() && indexClose < close.size()) {
           score = Math.max(score, score + open.get(indexOpen) + close.get(indexClose));
           indexOpen++;
           indexClose++;
       }
       return score;
   }

2. The second problem was exactly this one: Security Analysis Task - Two Passwords. Specific question not provided.