Daily_Problems-/day18_3.java at main · lakki0704/Daily_Problems- · GitHub

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class Solution {
    public static int goodStones(int n, int[] arr) {
        // code here


        int count =0;
        int[] visit = new int[n];

        for(int i=0; i<n; i++)
        {

          if(visit[i]==0)
          {
              check(arr, visit, i);
          }

        }

        for(int i=0; i<n ; i++)
        {
            if(visit[i]==2)
            {
                count++;
            }
        }

        return count;
    }


    public static int check(int[] arr, int[] visit , int index)
    {
        if(index<0 || index>=arr.length)
        {
            return 2; //safe
        }

        if(arr[index]==0)
        {
            return 1;
        }

        if(visit[index]!=0)
        {
            return visit[index];
        }

        visit[index]=1; //visited
        int new_i = index+ arr[index];

        return visit[index]=check(arr, visit, new_i);
    }
}