Reputation: 5302
I am trying to sort an array of strings according to their length using Arrays.sort()
, but this sorts the strings lexicographically rather than by length. Here is my code:
S = "No one could disentangle correctly"
String W[] = S.split(" ");
Arrays.sort(W);
After sorting :
correctly
could
disentangle
no
one
but what I want is
no //length = 2
one //length = 3
could //length = 4 and likewise
correctly
disentangle
How can I get the above output? Please give answer for JDK 1.7 & JDK1.8.
Upvotes: 24
Views: 69390
Reputation: 189
ArrayList<String> list=new ArrayList<>();
list.add("diamond");
list.add("silver");
list.add("gold");
System.out.println(list.stream().sorted(Comparator.comparingInt(String::length)).collect(Collectors.toList()));
output:
[gold, silver, diamond]
Upvotes: 0
Reputation: 71
If you prefer Streams in Java8 onwards then you could use -
String input = "This is a beautiful world";
String[] arr = Arrays.stream(input.split(" "))
.sorted(Comparator.comparingInt(String::length))
.toArray(String[]::new);
// prints output
System.out.println(Arrays.toString(arr));
The output is -
[a, is, This, world, beautiful]
Upvotes: 1
Reputation: 1
//possible but not recommended;
String sp[]="No one could disentangle correctly".split(" ");
for(int i=0;i<sp.length-1;i++)
{
for(int j=i+1;j<sp.length;j++)
{
if(sp[i].length()>sp[j].length())
{
String temp=sp[i];
sp[i]=sp[j];
sp[j]=temp;
}
}
}
for(String i:sp) //will print content of array sp
System.out.println(i);
Upvotes: 0
Reputation: 403
My answer is kind of irrelevant to this question (I wanted to sort and a list not an array) but since the answers provided here helped me solve my error, am going to leave it here for those that are facing the issue had.
Collections.sort(vehicles, (VehiclePayload vp1, VehiclePayload vp2)
-> Integer.compare(vp2.getPlateNumber().length(), vp1.getPlateNumber().length()));
Upvotes: 1
Reputation: 12347
For java 8 and above
Arrays.sort(W, (a, b)->Integer.compare(a.length(), b.length()));
A more concise way is to use Comparator.comparingInt from Mano's answer here.
Upvotes: 49
Reputation: 4452
Java 8 is pretty easy. as mentioned in the above answer. I was solving some problems on hackerrank and there they are using java 7. so I had to write the java7. That is selection sort. though time complexity is not great O(n^2) however it serves the purpose.
public static void main(String[] args) {
// I am taking list and again converting to array. please ignore. you can directly take array of string and apply the logic.
List<String> listOfString = new ArrayList<String>();
listOfString.add("because");
listOfString.add("can");
listOfString.add("do");
listOfString.add("must");
listOfString.add("we");
listOfString.add("what");
String[] w= new String[listOfString.size()];
for(int i =0;i <listOfString.size();i++) {
w[i] = listOfString.get(i);
}
// That is for java 8
//Arrays.sort(w, (a, b)->Integer.compare(a.length(), b.length()));
for (int i = 0; i < w.length; i++) {
for(int j=i+1;j<w.length;j++) {
String tempi = w[i];
String tempj = w[j];
if(tempj.length()<tempi.length()) {
w[i] =w[j];
w[j]=tempi;
}
}
}
// That is for printing the sorted array
for (int i = 0; i < w.length; i++) {
System.out.println(w[i]);
}
Output.
do
we
can
must
what
because
Upvotes: 1
Reputation: 51
Simply changing the parameter position we can sort in descending order.
Arrays.sort(W, (a,b)->b.length() - a.length());
Upvotes: 5
Reputation: 6846
import java.util.*;
class SortStringArray
{
public static void main (String[] args) throws java.lang.Exception
{
String S = "No one could disentangle correctly";
String W[] = S.split(" ");
Arrays.sort(W, new StringLengthComparator());
for(String str: W)
System.out.println(str); //print Your Expected Result.
}
}
class StringLengthComparator implements Comparator<String>{ //Custom Comparator class according to your need
@Override
public int compare(String str1, String str2) {
return str1.length() - str2.length();// compare length of Strings
}
}
Upvotes: 0
Reputation: 2270
If you are using JDK 1.8 or above then you could use lambda expression like matt answer. But if you are using JDK 1.7 or earlier version try to write a custom Comparator like this:
String S = "No one could disentangle correctly";
String W[] = S.split(" ");
Arrays.sort(W, new java.util.Comparator<String>() {
@Override
public int compare(String s1, String s2) {
// TODO: Argument validation (nullity, length)
return s1.length() - s2.length();// comparision
}
});
Upvotes: 19
Reputation: 22224
Alternative to and slightly simpler than matt's version
Arrays.sort(W, Comparator.comparingInt(String::length));
Upvotes: 37