Counting sort algo

What is counting sort algorithm .give me brief description about it

Counting sort is a sorting technique based on keys between a specific range. It works by counting the number of objects having distinct key values (kind of hashing). Then doing some arithmetic to calculate the position of each object in the output sequence.

Let us understand it with the help of an example.

For simplicity, consider the data in the range 0 to 9.

Input data: 1, 4, 1, 2, 7, 5, 2
  1) Take a count array to store the count of each unique object.
  Index:     0  1  2  3  4  5  6  7  8  9
  Count:     0  2  2  0   1  1  0  1  0  0

  2) Modify the count array such that each element at each index 
  stores the sum of previous counts. 
  Index:     0  1  2  3  4  5  6  7  8  9
  Count:     0  2  4  4  5  6  6  7  7  7

The modified count array indicates the position of each object in 
the output sequence.
 
  3) Output each object from the input sequence followed by 
  decreasing its count by 1.
  Process the input data: 1, 4, 1, 2, 7, 5, 2. Position of 1 is 2.
  Put data 1 at index 2 in output. Decrease count by 1 to place 
  next data 1 at an index 1 smaller than this index.

Here we assumed 1 indexed array
So now start with input array
1, 4, 1, 2, 7, 5, 2
Now count[1]=2
So place 1 at index 2(count[1]) in output array and do count[1]- - [- 1 - - - - - ]
Now place 4 at index 5(count[4]) and do count[4]- - [- 1 - - 4 - - ]
Now place 1 at index 1(count[1]) and do count[1]-- [1 1 - - 4 - - ]
Now place 2 at index 4(count[2]) and do count[2]-- [1 1 - 2 4 - - ]
Now place 7 at index 7(count[7]) and do count[7]-- [1 1 - 2 4 - 7 ]
Now place 5 at index 4(count[5]) and do count[5]-- [1 1 - 2 4 5 7 ]
Now place 2 at index 3(count[2]) and do count[2]-- [1 1 2 2 4 5 7 ]

it corrected my program i am also facing problem in counting sort i am getting segmentation fault

int freq[largest+1] = {0};

initialise this.line 11

i am tried many times to submit the code but not able to submit. Others problems are also submitting but not this one why it happens

@aman212yadav please look at this problem also

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