1208. Get Equal Substrings Within Budget

class Solution {
    public int equalSubstring(String s, String t, int maxCost) 
    {

        int[] arr = new int[s.length()];
        char[] ch = s.toCharArray(), target = t.toCharArray();

        for(int i=0; i<arr.length; i++)
        {
            arr[i] = Math.abs(ch[i] - target[i]);

        }

        int cost=0, start=0, end=0, result=0;

        while(start < arr.length && end <arr.length)
        {

            cost = cost+arr[end++];

            if(cost <= maxCost)
            {
                result = Math.max(result, end - start);

            }
            else
            {
                while(cost > maxCost)
                {
                    cost = cost-arr[start++];

                }
            }

        }

        return result;



        /*

        RUNTIME 6 MS , MEMORY 43.40 MB


        int[] diff = new int[s.length()];
        for(int i=0; i<s.length(); i++)
        {
            diff[i] = Math.abs(s.charAt(i) - t.charAt(i));

        }

        int start = 0, count = 0;

        for(int i=0; i<s.length(); i++)
        {
            maxCost = maxCost - diff[i];

            while(maxCost <0)
            {
                maxCost = maxCost + diff[start++];

            }

            count = Math.max(count, i-start+1);

        }

        return count;

        */


        /*

        RUNTIME 9 MS , MEMORY 42.95 MB

        int j = 0;
        for(int i = 0; i < s.length(); i++) 
        {
            maxCost -= Math.abs(s.charAt(i) - t.charAt(i));
            
            if(maxCost < 0)
            {
                maxCost += Math.abs(s.charAt(j) - t.charAt(j++));

            }

        }

        return s.length() - j;

*/

        
    }
}