cpp-flashcards/org/study_deck_02/dsa/stack/0682-baseball-game.org

#+ANKI_DECK: study_deck_02
* TODO 0682. Baseball Game :easy:
:PROPERTIES:
:NEETCODE: [[file:../../roadmap.org::*0682. Baseball Game][0682. Baseball Game]]
:END:

You are keeping the scores for a baseball game with strange rules. At the beginning of the game, you start with an empty record.

You are given a list of strings ~operations~, where ~operations[i]~ is the ~i^{th}~ operation you must apply to the record and is one of the following:

 - An integer ~x~.

 - Record a new score of ~x~.

 - ~'+'~.
 
 - Record a new score that is the sum of the previous two scores.

 - ~'D'~.
 
 - Record a new score that is the double of the previous score.

 - ~'C'~.
 
 - Invalidate the previous score, removing it from the record.

Return /the sum of all the scores on the record after applying all the operations/.

The test cases are generated such that the answer and all intermediate calculations fit in a *32-bit* integer and that all operations are valid.

*Example 1:*


#+begin_src
Input: ops = ["5","2","C","D","+"]
Output: 30
Explanation:
"5" - Add 5 to the record, record is now [5].
"2" - Add 2 to the record, record is now [5, 2].
"C" - Invalidate and remove the previous score, record is now [5].
"D" - Add 2 * 5 = 10 to the record, record is now [5, 10].
"+" - Add 5 + 10 = 15 to the record, record is now [5, 10, 15].
The total sum is 5 + 10 + 15 = 30.
#+end_src


*Example 2:*


#+begin_src
Input: ops = ["5","-2","4","C","D","9","+","+"]
Output: 27
Explanation:
"5" - Add 5 to the record, record is now [5].
"-2" - Add -2 to the record, record is now [5, -2].
"4" - Add 4 to the record, record is now [5, -2, 4].
"C" - Invalidate and remove the previous score, record is now [5, -2].
"D" - Add 2 * -2 = -4 to the record, record is now [5, -2, -4].
"9" - Add 9 to the record, record is now [5, -2, -4, 9].
"+" - Add -4 + 9 = 5 to the record, record is now [5, -2, -4, 9, 5].
"+" - Add 9 + 5 = 14 to the record, record is now [5, -2, -4, 9, 5, 14].
The total sum is 5 + -2 + -4 + 9 + 5 + 14 = 27.
#+end_src


*Example 3:*


#+begin_src
Input: ops = ["1","C"]
Output: 0
Explanation:
"1" - Add 1 to the record, record is now [1].
"C" - Invalidate and remove the previous score, record is now [].
Since the record is empty, the total sum is 0.
#+end_src


*Constraints:*

 - ~1 <= operations.length <= 1000~

 - ~operations[i]~ is ~"C"~, ~"D"~, ~"+"~, or a string representing an integer in the range ~[-3 * 10^{4}, 3 * 10^{4}]~.

 - For operation ~"+"~, there will always be at least two previous scores on the record.

 - For operations ~"C"~ and ~"D"~, there will always be at least one previous score on the record.

** TODO Approach
Write your approach here.

** TODO Python
#+begin_src python :lc-problem 682 :lc-lang python3
class Solution:
    def calPoints(self, operations: List[str]) -> int:
#+end_src

** TODO C++
#+begin_src cpp :lc-problem 682
class Solution {
public:
    int calPoints(vector<string>& operations) {
        
    }
};
#+end_src