求一随机算法！范围是26个大写字母，随机选择10个。

Question

求一随机算法！范围是26个大写字母，随机选择10个。

Answer 1

public static String[] getString(){
 String select[] ={"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};
 String[] select10 = new String[10];
 for(int i=0;i<select10.length;i++){
int j= (int)(Math.random()*26);
select10[i]=select[j];
 }  
 return select10;
}

Answer 2

public class T {
public static void main(String args[]) {
char allCapital[] = new char[26];
char result[] = new char[10];
for (int i = 0; i < 26; i++)
allCapital[i] = (char) (i + 65);
// can repeat
for (int i = 0; i < 10; i++)
result[i] = allCapital[(int) (Math.random() * 26)];
System.out.println(String.valueOf(result));
// no repeat
int n = allCapital.length;
char tmpArr[] = allCapital;
int random;
for (int i = 0; i < 10; i++) {
random = (int) (Math.random() * n);
result[i] = tmpArr[random];
tmpArr[random] = tmpArr[n - 1];
n--;
}
System.out.println(String.valueOf(result));
}
}