[Solved] Sort the String According to the Frequency of Character in Java
Problem Statement / TASK: You are given a string and your task is to sort the string according to the frequency of character and return the final string.
EXAMPLE 1 :
Input : "tree" Output : "eetr"
Explanation: The frequency of each character in the word is [1, 1, 2, 2] after sorting according to the frequency the output will be “eetr”.
EXAMPLE 2 :
Input : "hello" Output : "lleho"
Solution
Approach and Algorithm
- First, we will make the character array of the characters of the string.
- Then count the frequency of each character in the string.
- Taking the frequency as the main array sort the character array.
- Then make the string of that char array.
Java Program
Prerequisite:
Java Code:
import java.util.Arrays;
public class SortStringByFrequency {
public static void main(String[] args) {
String s = "tree";
int f[] = new int[s.length()];
char[] st = s.toCharArray();
for (int i = 0; i < st.length; i++) {
f[i] = countFrequency(st, st[i]);
}
// System.out.println(Arrays.toString(f));
System.out.println(sortArray(st, f));
}
public static int countFrequency(char[] a, char b) {
int count = 0;
for (char i : a){
if (i == b)
count++;
}
return count;
}
public static String sortArray(char[] a, int[] b) {
int t = 0;char c;
for (int i = 0; i < a.length - 1; i++) {
for (int j = 0;j < a.length - i - 1;j++) {
if (b[j] < b[j + 1]) {
t = b[j];
b[j] = b[j + 1];
b[j + 1] = t;
c = a[j];
a[j] = a[j + 1];
a[j + 1] = c;
}
}
}
System.out.println(Arrays.toString(b));
return Arrays.toString(a);
}
}
This is all about a code to sort the string according to the frequency of character. You can solve the above coding challenge in C/C++, Python or any of the programming languages of your choice.
