ArrayList
ArrayList<Integer> arr = new ArrayList<Integer>(); arr.size() arr.get(i) arr.add(i); arr.remove(i);
import java.util.ArrayList;
class Solution {
public int solution(int[][] board, int[] moves) {
int answer = 0;
ArrayList<Integer> arr = new ArrayList<Integer>();
for (int i=0; i<moves.length; i++) {
for (int j=0; j<board.length; j++) {
if (board[j][moves[i]-1]!=0) {
arr.add(board[j][moves[i]-1]);
if (arr.size()>1 && board[j][moves[i]-1]==arr.get(arr.size()-2)) {
arr.remove(arr.size()-1);
arr.remove(arr.size()-1);
answer+=2;
}
board[j][moves[i]-1]=0;
break;
}
}
}
return answer;
}
}