交個作業~~main函數就不寫了,分享一下方法
/**
* 3.對String泛型的List進行排序
* 創建String泛型的Lits,添加十個亂序的String元素
* 每條字符串的長度為10以內的隨即整數
* 每條字符串的每個字符都為隨即生成的字符,字符可以重復
* 每條隨即字符串不可重復
* 調用sort方法,再次輸出排序后的順序
*/
public void testSort3() {
List<String> strtinglist = new ArrayList<String>();
Random random = new Random();
Integer k;
String str = "abcedfghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
for (int i = 0; i < 10; i++) {
StringBuffer newstring = new StringBuffer();
do {
k = random.nextInt(10);
for (int j = 0; j < k+1; j++) {
newstring.append(str.charAt(random.nextInt(str.length())));
}
}while(strtinglist.contains(newstring));
System.out.println("將要添加字符串:"+"'"+newstring.toString()+"'");
strtinglist.add(newstring.toString());
}
System.out.println("----------排序前---------");
for (String string : strtinglist) {
System.out.println("元素"+string);
}
Collections.sort(strtinglist);
System.out.println("----------排序后---------");
for (String string : strtinglist) {
System.out.println("元素"+string);
}
}
2020-07-21
????public?void?testSort()?{ ????????//?隨機生成十條字符串 ????????for(int?i=0;?i<10;?i++)?{ ????????????StringBuilder?str?=?new?StringBuilder(); ????????????Random?random?=?new?Random(); ????????????//?長度為10以內的隨機整數 ????????????int?l?=?random.nextInt(10); ????????????for(int?j=0;?j<l;?j++)?{ ????????????????char?ranChar?=?(char)?Math.round(Math.random()*51+65); ????????????????//?去掉特殊字符 ????????????????if(ranChar<91?||?ranChar>96)? ????????????????????str.append(ranChar); ????????????} ????????????strings.add(str.toString()); ????????} ????????System.out.println("------------排序前-------------"); ????????for(String?str?:?strings)?{ ????????????System.out.println(strings.indexOf(str)+1+":"+str); ????????} ????????System.out.println("------------排序后-------------"); ????????Collections.sort(strings); ????????for(String?str?:?strings)?{ ????????????System.out.println(strings.indexOf(str)+1+":"+str); ????????} ????}2020-07-05
這樣好像不太行 應該每次循環的最后清空一次newstring
int nsl= newstring.length();
newstring.delete(0,nsl);