import java.util.*;
class Solution {
public int[] solution(int[] arr) {
ArrayList<Integer> stk = new ArrayList<Integer>();
int i = 0;
while(arr.length > i){
if(stk.isEmpty() || stk.get(stk.size() -1 ) < arr[i]){
stk.add(arr[i]);
i++;
}else{
stk.remove(stk.size()-1);
}
}
int[] result = new int[stk.size()];
for(int j = 0; j < stk.size(); j++){
result[j] = stk.get(j);
}
return result;
}
}