1209. Remove All Adjacent Duplicates in String II

class Solution {
    public String removeDuplicates(String s, int k) {
        Stack<Character> main = new Stack<>();
        
        for(char c: s.toCharArray()){
            Stack<Character> temp = new Stack<>();
            temp.push(c);
            
            while(!main.isEmpty() && main.peek()==c){
                temp.push(main.pop());
            }
            
            if(temp.size()!=k){
                while(!temp.isEmpty()){
                    main.push(temp.pop());
                }
            }
        }
        
        StringBuilder sb= new StringBuilder();
        
        while(!main.isEmpty()){
            sb.append(main.pop());
        }
        
        return sb.reverse().toString();
    }
}

class Solution {
    public String removeDuplicates(String s, int k) {
        Stack<int[]> main = new Stack<>();
        
        for(char c: s.toCharArray()){
            if(!main.isEmpty() && main.peek()[0] == c){
                main.peek()[1]++;
            }
            else{
                main.push(new int[]{c,1});
            }
            
            if(main.peek()[1]==k){
                main.pop();
            }
        }
        
        StringBuilder sb= new StringBuilder();
        
        while(!main.isEmpty()){
            int[] top = main.pop();
            
            while(top[1]-->0)
                sb.append((char) top[0]);
        }
        
        return sb.reverse().toString();
    }
}

class Solution {
    public String removeDuplicates(String s, int k) {
        int count = 1;
        for(int i=1;i<s.length();i++){
            if(s.charAt(i)==s.charAt(i-1)){
                count++;
            }
            else{
                count=1;
            }
            
            if(count==k){
                String reduced = s.substring(0,i-k+1) + s.substring(i+1);
                return removeDuplicates(reduced,k);
            }
        }
        
        return s;
    }
}