我有:
List<String> alphabet; (contains 26 unique characters as elements, for example
qwertyuiosapdfghjklzcxvbnm)
List<String> wordsToArrange; contains words as elements, for example:
- apple
- stream
- posthouse
- sea
- seed
我需要根据我制作的字母排列单词。
我目前的方法是循环。
alphabet(i) compare it with all the words charAt(0)
if only 1 is found i put it to a new list arrangedList
but if 2 is found i go alphabet(i+1) till the letter is found and now i can put them in a right order to arrangedList....
then move back to alphabet(i+1) till alphabet(26) and now all should be arranged correctly...
我为这段代码写了一些基础,但我想在开始严肃的“循环”之前询问其他方法是什么。
谢谢!
答案 0 :(得分:0)
我会:
'a'
是该字符串的第11个字母,因此请将其映射到'k'
'b'
是该字符串的第24个字母,因此请将其映射到'x'
Collections.sort
'k' -> 'a'; 'x' -> 'b'
。答案 1 :(得分:0)
我使用Java 8的过滤器和流来过滤掉以某个字符开头的那些..然后我对结果进行排序。如果它需要在一个数组中,那么结合结果。
import java.util.Arrays;
/**
* Created by Brandon on 2016-04-17.
*/
public class Main {
public static void main(String[] args) {
String[] array = new String[]{"apple", "stream", "posthouse", "sea", "seed"};
//char[] indices = new char[]{'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'};
char[] indices2 = new char[]{'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p', 'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l', 'z', 'x', 'c', 'v', 'b', 'n', 'm'};
for (char key : indices2) {
String[] result = Arrays.stream(array).filter(value -> value.charAt(0) == key).toArray(length -> new String[length]);
if (result.length > 0) {
Arrays.sort(result);
System.out.println(Arrays.toString(result));
}
}
}
}
如果使用indices
,则结果为:
[apple]
[posthouse]
[sea, seed, stream]
如果使用indices2
,则结果为:
[posthouse]
[apple]
[sea, seed, stream]
答案 2 :(得分:0)
如何将String包装在一个实现可比较的新类中?
可能是我未测试的一些边缘案例错误。
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class CompString {
public static void main(String[] args) {
List<ComparableString> list = new ArrayList<ComparableString>();
list.add(new ComparableString("apple"));
list.add(new ComparableString("stream"));
list.add(new ComparableString("posthouse"));
list.add(new ComparableString("sea"));
list.add(new ComparableString("seed"));
Collections.sort(list);
System.out.println(list);
}
}
class ComparableString implements Comparable<ComparableString> {
String str;
static String sortOrder = "qwertyuiosapdfghjklzcxvbnm";
public ComparableString(String string) {
str = string;
}
@Override
public String toString() {
return str;
}
@Override
public int compareTo(ComparableString other) {
for (int i = 0; i < Math.min(this.str.length(), other.str.length()); i++) {
int thisOrder = ComparableString.sortOrder.indexOf(this.str.charAt(i));
int thatOrder = ComparableString.sortOrder.indexOf(other.str.charAt(i));
int order = thisOrder - thatOrder;
if (order != 0) {
return order;
}
}
if (this.str.length() > other.str.length()) {
return -1;
} else if (this.str.length() < other.str.length()) {
return 1;
}
return 0;
}
}