public class HelloWorld {
??? public static void main(String[] args) {
??????? // 創(chuàng)建一個(gè)空的StringBuilder對(duì)象
??????? StringBuilder str = new StringBuilder();
??????? // 追加字符串
??????? str.append("jaewkjldfxmopzdm");
??????? // 從后往前每隔三位插入逗號(hào)
??????? for(int i=str.length();i>0;i--){
??????????? if((i-1)%3==0){
??????????????? str.insert(i,",");
??????????? }
??????? }
??????? str.deleteCharAt(str.length()-1);
??????? // 將StringBuilder對(duì)象轉(zhuǎn)換為String對(duì)象并輸出
??????? System.out.print(str.toString());
??? }
}

這個(gè)我寫的，網(wǎng)站不能識(shí)別，是可以的，網(wǎng)站存在了一些不足呀