[LeetCode 38] Count and Say

题目链接：count-and-say

/**
 *
		The count-and-say sequence is the sequence of integers beginning as follows:
		1, 11, 21, 1211, 111221, ...

		1 is read off as "one 1" or 11.
		11 is read off as "two 1s" or 21.
		21 is read off as "one 2, then one 1" or 1211.
 *
 */

public class CountandSay {

//	18 / 18 test cases passed.
//	Status: Accepted
//	Runtime: 273 ms
//	Submitted: 2 minutes ago

    static String countAndSay(int n) {
        String s = "1";
    	for (int i = 1; i < n; i++)
			s = countAndSay(s);
        return s;
    }
    static String countAndSay(String str) {
    	String say = "";
    	int count = 1;
    	for (int i = 0; i < str.length() - 1; i++) {
			if(str.charAt(i) == str.charAt(i + 1)) count++;
			else {
				say  += count + "" + str.charAt(i);
				count = 1;
			}
		}
		say  += count + "" + str.charAt(str.length() - 1);
		return say;
    }
	public static void main(String[] args) {
		System.out.println(countAndSay(4));
	}

}