|
|
package class03;
|
|
|
|
|
|
import java.util.HashSet;
|
|
|
|
|
|
public class Code02_HowManyTypes {
|
|
|
|
|
|
/*
|
|
|
* 只由小写字母（a~z）组成的一批字符串，都放在字符类型的数组String[] arr中，
|
|
|
* 如果其中某两个字符串，所含有的字符种类完全一样，就将两个字符串算作一类 比如：baacba和bac就算作一类
|
|
|
* 虽然长度不一样，但是所含字符的种类完全一样（a、b、c） 返回arr中有多少类？
|
|
|
*
|
|
|
*/
|
|
|
|
|
|
public static int types1(String[] arr) {
|
|
|
HashSet<String> types = new HashSet<>();
|
|
|
for (String str : arr) {
|
|
|
char[] chs = str.toCharArray();
|
|
|
boolean[] map = new boolean[26];
|
|
|
for (int i = 0; i < chs.length; i++) {
|
|
|
map[chs[i] - 'a'] = true;
|
|
|
}
|
|
|
String key = "";
|
|
|
for (int i = 0; i < 26; i++) {
|
|
|
if (map[i]) {
|
|
|
key += String.valueOf((char) (i + 'a'));
|
|
|
}
|
|
|
}
|
|
|
types.add(key);
|
|
|
}
|
|
|
return types.size();
|
|
|
}
|
|
|
|
|
|
public static int types2(String[] arr) {
|
|
|
HashSet<Integer> types = new HashSet<>();
|
|
|
for (String str : arr) {
|
|
|
char[] chs = str.toCharArray();
|
|
|
int key = 0;
|
|
|
for(int i = 0 ; i < chs.length;i++) {
|
|
|
key |= (1 << (chs[i] - 'a'));
|
|
|
}
|
|
|
types.add(key);
|
|
|
}
|
|
|
return types.size();
|
|
|
}
|
|
|
|
|
|
// for test
|
|
|
public static String[] getRandomStringArray(int possibilities, int strMaxSize, int arrMaxSize) {
|
|
|
String[] ans = new String[(int) (Math.random() * arrMaxSize) + 1];
|
|
|
for (int i = 0; i < ans.length; i++) {
|
|
|
ans[i] = getRandomString(possibilities, strMaxSize);
|
|
|
}
|
|
|
return ans;
|
|
|
}
|
|
|
|
|
|
// for test
|
|
|
public static String getRandomString(int possibilities, int strMaxSize) {
|
|
|
char[] ans = new char[(int) (Math.random() * strMaxSize) + 1];
|
|
|
for (int i = 0; i < ans.length; i++) {
|
|
|
ans[i] = (char) ((int) (Math.random() * possibilities) + 'a');
|
|
|
}
|
|
|
return String.valueOf(ans);
|
|
|
}
|
|
|
|
|
|
public static void main(String[] args) {
|
|
|
int possibilities = 5;
|
|
|
int strMaxSize = 10;
|
|
|
int arrMaxSize = 100;
|
|
|
int testTimes = 500000;
|
|
|
System.out.println("test begin, test time : " + testTimes);
|
|
|
for (int i = 0; i < testTimes; i++) {
|
|
|
String[] arr = getRandomStringArray(possibilities, strMaxSize, arrMaxSize);
|
|
|
int ans1 = types1(arr);
|
|
|
int ans2 = types2(arr);
|
|
|
if (ans1 != ans2) {
|
|
|
System.out.println("Oops!");
|
|
|
}
|
|
|
}
|
|
|
System.out.println("test finish");
|
|
|
|
|
|
}
|
|
|
|
|
|
}
|
