Count Frequency in a range

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Problem statement

You are given an array 'arr' of length 'n' containing integers within the range '1' to 'x'.

Your task is to count the frequency of all elements from 1 to n.

Note:

You do not need to print anything. Return a frequency array as an array in the function such that index 0 represents the frequency of 1, index 1 represents the frequency of 2, and so on.

Example:

Input: ‘n’ = 6 ‘x’ = 9 ‘arr’ = [1, 3, 1, 9, 2, 7]    
Output: [2, 1, 1, 0, 0, 0]
Explanation: Below Table shows the number and their counts, respectively, in the array
Number         Count 
 1                2
 2              1
 3                1
 4                0
 5                0
 6                0

Detailed explanation ( Input/output format, Notes, Images )

Input Format:

The first line contains two integers, ‘n’ and ‘x’.
The following line contains ‘n’ integers and the array ‘arr’.

Output format:

Return the frequency array.

Sample Input 1:

6 4
1 3 4 3 4 1

Sample Output 1:

2 0 2 2 0 0

Explanation Of Sample Input 1 :

Frequency table:
Number         Count 
 1                2
 2              0
 3                2
 4                2
 5                0
 6                0

Sample Input 2 :

5 5
1 2 3 4 5

Sample Output 2 :

1 1 1 1 1

Explanation Of Sample Input 2 :

Frequency table:
Number         Count 
 1                1
 2              1
 3                1
 4                1
 5                1

Constraints:

1  <= n <= 10^5
1  <= x <= 10^5
1 <= arr[i] <= x

Hints:

1. Since the range of the elements is known, we can iterate over the range.
2. Since the bounds of the elements are known, a frequency array can be maintained.
3. Try to use the input array as the answer array itself.

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