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Given an array A (may contain duplicates) of N elements and a positive integer K. The task is to count the number of elements which occurs exactly floor(N/K) times in the array.

Input:
First line of input contains number of testcases. For each testcase, there will be two lines, first of which contains N and K and second line contains array elements.

Output:
For each testcase, print the count of elements in the array which occurs exactly floor(N/K) times.

Constraints:
1 <= T <= 100
1 <= N <= 103
1 <= Ai <= 103
1 <= K <= 103

for test case:
1
5 2
1 1 1 1000 1000

What I have tried:

```#include <bits/stdc++.h>
using namespace std;
int countSpecials(int[], int, int);
int main() {
int testcase;
cin >> testcase;
while(testcase--){
int sizeof_array, K;
cin >> sizeof_array >> K;
int arr[sizeof_array];
for(int i = 0;i<sizeof_array;i++){
cin >> arr[i];
}
cout << countSpecials(arr, sizeof_array, K) << endl;
}
return 0;
}
int countSpecials(int arr[], int sizeof_array, int K){

int f = floor(sizeof_array/K), count = 0;
int i,key[1000]={0},p;
for(i=0;i<sizeof_array;i++)
p=arr[i];
{
if(p>=1 && p<=1000)
key[p]++;
}
for(i=1;i<sizeof_array;i++)
{
if(f==key[i])
count++;
}
return count;
}```
Posted
Updated 10-Dec-18 10:52am
v3
CHill60 10-Dec-18 9:36am

If it is how to fix the error then give us all the details of the error
Prateek Krishna 10-Dec-18 9:39am
sorry
my updated question is "it is showing wrong answer"
how to correct it?

## Solution 1

Quote:
my updated question is "it is showing wrong answer"
how to correct it?
Simple: Write the correct code.

Compiling does not mean your code is right! :laugh:
Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send.

So now you enter the second stage of development (in reality it's the fourth or fifth, but you'll come to the earlier stages later): Testing and Debugging.

Start by looking at what it does do, and how that differs from what you wanted. This is important, because it give you information as to why it's doing it. For example, if a program is intended to let the user enter a number and it doubles it and prints the answer, then if the input / output was like this:
```Input   Expected output    Actual output
1            2                 1
2            4                 4
3            6                 9
4            8                16```
Then it's fairly obvious that the problem is with the bit which doubles it - it's not adding itself to itself, or multiplying it by 2, it's multiplying it by itself and returning the square of the input.
So with that, you can look at the code and it's obvious that it's somewhere here:
C#
```int Double(int value)
{
return value * value;
}```

Once you have an idea what might be going wrong, start using the debugger to find out why. Put a breakpoint on the first line of the method, and run your app. When it reaches the breakpoint, the debugger will stop, and hand control over to you. You can now run your code line-by-line (called "single stepping") and look at (or even change) variable contents as necessary (heck, you can even change the code and try again if you need to).
Think about what each line in the code should do before you execute it, and compare that to what it actually did when you use the "Step over" button to execute each line in turn. Did it do what you expect? If so, move on to the next line.
If not, why not? How does it differ?
Hopefully, that should help you locate which part of that code has a problem, and what the problem is.
This is a skill, and it's one which is well worth developing as it helps you in the real world as well as in development. And like all skills, it only improves by use!

## Solution 2

Your `countSpecials` function is incorrect.

Quote:
for(i=0;i<sizeof_array;i++)
p=arr[i];
{
if(p>=1 && p<=1000)
key[p]++;
}
This probably executes the way you don't expect:
• Iteration is applied on to `p=arr[i];` statememt.
• `key[p]++` is out-of-bounds when `p = 1000`.

Try
C++
```#include <iostream>
#include <vector>
#include <array>
using namespace std;

constexpr size_t L = 1000;

size_t count_specials(const vector<int> & v, size_t k)
{
int f = v.size()/k;
array<int, L> freq{};
for (auto x : v)
++freq[x-1];

size_t count = 0;

for (auto x : freq)
if ( x == f)
++count;

return count;
}

int main()
{
size_t T;
cin >> T;
while (T--)
{
size_t N, K;
cin >> N >> K;
vector <int > v;
for ( size_t n=0; n<N; ++n)
{
int x;
cin >> x;
v.push_back(x);
}
cout << count_specials(v, K);
}
}```

v2

## Solution 3

First of all, wen you ask help on a problem you found on internet, it is wise to give a link to original problem.
Count the Specials - Java | Practice | GeeksforGeeks[^]

Learn to indent properly your code, it show its structure and it helps reading and understanding. It also helps spotting structures mistakes.
C++
```#include <bits/stdc++.h>
using namespace std;
int countSpecials(int[], int, int);
int main() {
int testcase;
cin >> testcase;
while(testcase--){
int sizeof_array, K;
cin >> sizeof_array >> K;
int arr[sizeof_array];
for(int i = 0;i<sizeof_array;i++){
cin >> arr[i];
}
cout << countSpecials(arr, sizeof_array, K) << endl;
}
return 0;
}
int countSpecials(int arr[], int sizeof_array, int K){

int f = floor(sizeof_array/K), count = 0;
int i,key[1000]={0},p;
for(i=0;i<sizeof_array;i++)
p=arr[i];
{
if(p>=1 && p<=1000)
key[p]++;
}
for(i=1;i<sizeof_array;i++)
{
if(f==key[i])
count++;
}
return count;
}```

Professional programmer's editors have this feature and others ones such as parenthesis matching and syntax highlighting.
ultraedit[^]
-----
Your code do not behave the way you expect, or you don't understand why !

There is an almost universal solution: Run your code on debugger step by step, inspect variables.
The debugger is here to show you what your code is doing and your task is to compare with what it should do.
There is no magic in the debugger, it don't know what your code is supposed to do, it don't find bugs, it just help you to by showing you what is going on. When the code don't do what is expected, you are close to a bug.
To see what your code is doing: Just set a breakpoint and see your code performing, the debugger allow you to execute lines 1 by 1 and to inspect variables as it execute.

Debugger - Wikipedia, the free encyclopedia[^]

Mastering Debugging in Visual Studio 2010 - A Beginner's Guide[^]
Basic Debugging with Visual Studio 2010 - YouTube[^]

1.11 — Debugging your program (stepping and breakpoints) | Learn C++[^]

The debugger is here to only show you what your code is doing and your task is to compare with what it should do.