Goal Parser Interpretation

给一个string, 要变成另一个string, 规则是看到G 返回G, 看到() 返回o, 看到(al)返回al.

class Solution {
    public String interpret(String command) {
        StringBuilder sb = new StringBuilder();
        int i = 0;
        int n = command.length();
        while(i < n) {
            if(i + 1 <= n && command.substring(i, i+1).equals("G")){
                sb.append("G");
                i += 1;
            } else if(i + 2 <= n && command.substring(i, i+2).equals("()")){
                sb.append("o");
                i += 2;
            } else if(i + 4 <= n && command.substring(i, i+4).equals("(al)")){
                sb.append("al");
                i += 4;
            }
        }
        return sb.toString();
    }
}