Leetcode【38】Count and Say

class Solution {
    public String countAndSay(int n) {
        if(n == 1){
            return "1";
        }
        String str = countAndSay(n-1) + "*";// 这样末尾的数才能被循环处理到
        char[] str_c = str.toCharArray();
        int count = 1;
        StringBuilder temp = new StringBuilder();
        int i = 0;
        while (i < str_c.length-1) {
            if(str_c[i] == str_c[i+1]){
                count++;  //遇到相同的计数器加
                i++;
            }else{
                temp.append(Integer.toString(count)+ str_c[i]);
                // 遇到不同的，先append计数器的值，再append最后一个相同的值
                // temp.append("" + count + str_c[i]);
                count = 1;
                i++;
            }
        }
        return temp.toString();
    }
}