题目有点问题。运行结果是Java文件文无效,我输出的就是无效但是,提示java文件名正确,再试试。。。
2016-06-21
Random random=new Random();
Integer k;
List<Integer> number = new ArrayList();
for(int i=0;i<3;i++){
do{
k=random.nextInt(1000);
}while(number.contains(k));
number.add(k);
}
studentList.add(new Student(number.get(0)+"","Mike"));
Integer k;
List<Integer> number = new ArrayList();
for(int i=0;i<3;i++){
do{
k=random.nextInt(1000);
}while(number.contains(k));
number.add(k);
}
studentList.add(new Student(number.get(0)+"","Mike"));
2016-06-20
当字符串长度发生变化时(为3的整数倍)同样适用:
int strLength = str.length();
int beishu=strLength/3;
int yushu=strLength%3;
int k=0 ;
if (yushu==0)
k=k+1;
for ( int i=beishu;i>k;i--){
int index = i*3 + yushu - 3;
str.insert(index,",");
}
int strLength = str.length();
int beishu=strLength/3;
int yushu=strLength%3;
int k=0 ;
if (yushu==0)
k=k+1;
for ( int i=beishu;i>k;i--){
int index = i*3 + yushu - 3;
str.insert(index,",");
}
2016-06-18
看卡是不是这样做的
public static void main(String[] args) {
String s= "tgipoifhakajiiaaiaajaakaclamka";
int num = 0;
for(int i=0;i<s.length();i++){
//s.charAt(i)表示获取每个字符,==是否等于"a"
if(s.charAt(i)=='a'){
num++;
}
}
System.out.println("字符a出现的次数:"+num);
}
public static void main(String[] args) {
String s= "tgipoifhakajiiaaiaajaakaclamka";
int num = 0;
for(int i=0;i<s.length();i++){
//s.charAt(i)表示获取每个字符,==是否等于"a"
if(s.charAt(i)=='a'){
num++;
}
}
System.out.println("字符a出现的次数:"+num);
}
2016-06-17
https://github.com/CoderMengLi/PokerGame 欢迎下载交流,视频中说的自定义异常那个没弄懂,hashCode()也没太懂,还请大家指点
2016-06-17