给定一个长度,随机产生一个该长度的字符串,由大写,小写字母以及数字组成
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
while (true){
int num=input.nextInt();
if(num>0){
System.out.println(getStr(num));
}else{
break;
}
}
}
static String getStr(int num){
Random random=new Random();
int flag=0;
StringBuilder stringBuilder=new StringBuilder();
int i=0;
do{
flag=random.nextInt(3);
if(flag==0){
stringBuilder.append(random.nextInt(10));
}else if(flag==1){
stringBuilder.append((char)(65+random.nextInt(26)));
}else{
stringBuilder.append((char)(97+random.nextInt(26)));
}
i++;
}while(i<num);
return stringBuilder.toString();
}