int[] nums = new int[10];
int x = (int)(Math.random()*10);//這里要注意必須對Math.random()*10加上小括號,否則Math.random()會被強制轉換成int類型,x只能是0了,涉及到運算方向的問題
(int num:nums
int x = (int)(Math.random()*10);//這里要注意必須對Math.random()*10加上小括號,否則Math.random()會被強制轉換成int類型,x只能是0了,涉及到運算方向的問題
(int num:nums
2018-04-08
StringBuilder str = new StringBuilder();
for(int i = str.length()-3;i>0;i-=3)
str.insert(i,',');
for(int i = str.length()-3;i>0;i-=3)
str.insert(i,',');
2018-04-07
int index = fileName.lastIndexOf(".");
String prefix =fileName.substring(index+1,fileName.length());
index!=(-1) && index!=0 && prefix.equals("java")
int index2 = email.indexOf('@');
String prefix =fileName.substring(index+1,fileName.length());
index!=(-1) && index!=0 && prefix.equals("java")
int index2 = email.indexOf('@');
2018-04-07
自己做才發現好難,最笨的方法,歡迎幕友一起學習http://www.xianlaiwan.cn/opus/resource?opus_id=3501
2018-04-07
List<String> sList = new ArrayList<String>();
String str="abcdefghijklmnopqrstuvwxyzABCDEFGHIJ......62個";
int n;
fori=0;i<10;i++){
StringBuffer strB=new StringBuffer();
Random r= new Random();
for(j=0;j<random.nextInt(10)+1;j++){
n=r.nextInt(62);
strB.append(str.charAt(n));
}
String str="abcdefghijklmnopqrstuvwxyzABCDEFGHIJ......62個";
int n;
fori=0;i<10;i++){
StringBuffer strB=new StringBuffer();
Random r= new Random();
for(j=0;j<random.nextInt(10)+1;j++){
n=r.nextInt(62);
strB.append(str.charAt(n));
}
2018-04-05
public class HelloWorld {
public static void main(String[] args) {
StringBuilder str = new StringBuilder();
// 追加字符串
str.append("jaewkjldfxmopzdm");
for (int i=str.length()-3;i>=0;i-=3)
{
str.insert(i,',');
}
System.out.print(str.toString());
}
}
public static void main(String[] args) {
StringBuilder str = new StringBuilder();
// 追加字符串
str.append("jaewkjldfxmopzdm");
for (int i=str.length()-3;i>=0;i-=3)
{
str.insert(i,',');
}
System.out.print(str.toString());
}
}
2018-04-03