Problem

Implement Count And Say function. For example, first, let user input a number, say 1. Then, the function will generate the next 10 numbers which satisfy this condition: ,1, 11,21,1211,111221,312211...

explanation: first number 1, second number is one 1, so 11. Third number is two 1(previous number), so 21. next number one 2 one 1, so 1211 and so on...

Solution

public String countAndSay(int n) {    if (n <= 0)        return "";    String curRes = "1";    int start = 1;    while (start < n) {        StringBuffer sb = new StringBuffer();        int cnt = 1;        for (int i = 1; i < curRes.length(); i++) {            if (curRes.charAt(i) == curRes.charAt(i - 1)) {                cnt++;            }            else {                sb.append(cnt);                sb.append(curRes.charAt(i - 1));                cnt = 1;            }        }        sb.append(cnt);        sb.append(curRes.charAt(curRes.length() - 1));        curRes = sb.toString();        start++;    }    return curRes;}