Leetocde#38||Count and Say

public class Solution {    public String countAndSay(int n) {        if (n < 1) {            return null;        }                String result = "1";        int t = n;                while (t > 1) {            char[] arr = result.toCharArray();            StringBuilder sb = new StringBuilder();                        for (int i = 0; i < arr.length; i++) {                int count = 1;                                while ((i + 1) < arr.length && arr[i] == arr[i + 1]) {                    count ++;                    i++;                }                                sb.append(count);                sb.append(arr[i]);                                result = sb.toString();            }            t--;        }                  return result;    }}