Java在OJ时运行超时的问题解决方案

class Reader {
    static BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
    static StringTokenizer tokenizer = new StringTokenizer("");
    static String nextLine() throws IOException{// 读取下一行字符串
        return reader.readLine();
    }
    static String next() throws IOException {// 读取下一个字符串
        while (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine());
        }
        return tokenizer.nextToken();
    }
    static int nextInt() throws IOException {// 读取下一个int型数值
        return Integer.parseInt(next());
    }
    static double nextDouble() throws IOException {// 读取下一个double型数值
        return Double.parseDouble(next());
    }
}

StringBuilder s=new StringBuilder();       //建立StringBuilder的两种方式
StringBuilder s1=new StringBuilder("Adam");
s.append("hahaha"); //在字符串末尾添加字符串
s.insert(3,"hhh");  //在字符串中的位置插入字符串
s.setCharAt(1, 's'); //将字符串中指定位置字符替换
String s3=s.toString(); //转换为String