Sort an array of strings according to string lengths using Map

Given an array of strings, we need to sort the array in increasing order of string lengths, using Map Data Structure.


Input: str[] = {“GeeksforGeeeks”, “I”, “from”, “am”}
Output: I am from GeeksforGeeks

Input: str[] = {“You”, “are”, “beautiful”, “looking”}
Output: You are looking beautiful

Approach: The given approach is for Java using TreeMap

Below is the implementation of the above approach:





// Java program to sort an Array of
// Strings according to their lengths
// using Map
import java.util.*;
import java.util.Map.Entry;
public class GFG {
    // Function to Sort the array of string
    // according to lengths using Map
    static String[] sort(String[] str, int n)
        TreeMap<Integer, ArrayList<String> > map
            = new TreeMap<Integer, ArrayList<String> >();
        for (int i = 0; i < n; i++) {
                            new ArrayList<String>());
        int temp = 0;
        for (Entry<Integer, ArrayList<String> >
                 e : map.entrySet()) {
            for (int i = 0; i < e.getValue().size(); i++) {
                str[temp] = e.getValue().get(i);
        return str;
    // Function to print the sorted array of string
    static void printArraystring(String str[], int n)
        for (int i = 0; i < n; i++)
            System.out.print(str[i] + " ");
    // Driver function
    public static void main(String args[])
        String[] arr = { "GeeksforGeeks",
                         "I", "from", "am" };
        int n = arr.length;
        // Function to perform sorting
        arr = sort(arr, n);
        // Calling the function to print result
        printArraystring(arr, n);

I am from GeeksforGeeks

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