38.Count and Say

http://blog.csdn.net/xygy8860/article/details/46821417

Understand the Question first.

class Solution {
    public String countAndSay(int n) {
        if(n == 1){
            return "1";
        }
        // * is used to compare c[i] with c[i + 1];
        String str = countAndSay(n - 1) + '*';
        char[] c = str.toCharArray();
        int cnt = 1;
        StringBuilder sb = new StringBuilder();
        for(int i = 0; i < c.length - 1; i++){
            if(c[i] == c[i + 1]){
                cnt++;
            }
            else{
                sb.append(cnt);
                sb.append(c[i]);
                cnt = 1;
            }
        }
        return sb.toString();
    }
}