Count the number of clumps in the given Array

Given an array arr[] of N integers, the task is to count the number of clumps in the given array.

Clump is defined as a series of 2 or more adjacent elements of the same value.

Examples:

Input: arr[] = { 13, 15, 66, 66, 37, 8, 8, 11, 52 }; 
Output: 2 
Explanation:
There are two clumps in the given array {66, 66} and {8, 8}.
Input: arr[] = {1, 2, 1, 4, 3, 2} 
Output: 0 
Explanation:
There are no clumps in the given array. 

Approach: In order to solve the problem, we need to follow the following steps: 

1. Traverse through the array and check for any occurrence of same element on two consecutive indices.
2. For any such occurrence, loop until a different number occurs.
3. Increase the count of clumps by 1 only after execution of step 2. If the entire array isn’t traversed yet, repeat the above steps for the following elements.
4. Print the final count of clumps after entire array traversal.

Below is the implementation of the above approach:

C++

// C++ program to calculate
// the number of clumps in
// an array
#include <bits/stdc++.h>
using namespace std;

// Function to count the number of
// clumps in the given array arr[]
int countClumps(int arr[], int N)
{

    // Initialise count of clumps as 0
    int clumps = 0;

    // Traverse the arr[]
    for (int i = 0; i < N - 1; i++) {

        int flag = 0;
        // Whenever a sequence of same
        // value is encountered
        while (arr[i] == arr[i + 1]) {
            flag = 1;
            i++;
        }

        if (flag)
            clumps++;
    }

    // Return the count of clumps
    return clumps;
}
// Driver Code
int main()
{

    // Given array
    int arr[] = { 13, 15, 66, 66, 66, 37, 37,
                  8, 8, 11, 11 };

    // length of the given array arr[]
    int N = sizeof(arr) / sizeof(arr[0]);

    // Function Call
    cout << countClumps(arr, N) << '\n';
    return 0;
}

Java

// Java program for the above approach
class Test {

    // Given array arr[]
    static int arr[] = { 13, 15, 66, 66, 66,
                         37, 37, 8, 8, 11, 11 };

    // Function to count the number of
    // clumps in the given array arr[]
    static int countClumps()
    {
        int l = arr.length;

        // Initialise count of clumps as 0
        int clumps = 0;

        // Traverse the arr[]
        for (int i = 0; i < l - 1; i++) {

            int flag = 0;
            // Whenever a sequence of same
            // value is encountered
            while (i < l - 1
                   && arr[i] == arr[i + 1]) {
                flag = 1;
                i++;
            }

            if (flag == 1)
                clumps++;
        }

        // Return the count of clumps
        return clumps;
    }

    // Driver Code
    public static void main(String[] args)
    {

        // Function Call
        System.out.println(countClumps());
    }
}

Python3

# Python3 program to calculate
# the number of clumps in
# an array

# Function to count the number of
# clumps in the given array arr[]
def countClumps(arr, N):

    # Initialise count of clumps as 0
    clumps = 0

    # Traverse the arr[]
    i = 0
    while(i < N - 1):

        flag = 0

        # Whenever a sequence of same
        # value is encountered
        while (i + 1 < N and
               arr[i] == arr[i + 1]):
            flag = 1
            i += 1

        if (flag):
            clumps += 1

        i += 1

    # Return the count of clumps
    return clumps

# Driver Code

# Given array
arr = [ 13, 15, 66, 66, 66,
        37, 37, 8, 8, 11, 11 ]

# length of the given array arr[]
N = len(arr)

# Function Call
print(countClumps(arr, N))

# This code is contributed by yatin

C#

// C# program for the above approach
using System;
class GFG{

// Given array arr[]
static int []arr = { 13, 15, 66, 66, 66,
                     37, 37, 8, 8, 11, 11 };

// Function to count the number of
// clumps in the given array arr[]
static int countClumps()
{
    int l = arr.Length;

    // Initialise count of clumps as 0
    int clumps = 0;

    // Traverse the arr[]
    for (int i = 0; i < l - 1; i++)
    {
        int flag = 0;

        // Whenever a sequence of same
        // value is encountered
        while (i < l - 1 && arr[i] == arr[i + 1])
        {
            flag = 1;
            i++;
        }

        if (flag == 1)
            clumps++;
    }

    // Return the count of clumps
    return clumps;
}

// Driver Code
public static void Main()
{

    // Function Call
    Console.WriteLine(countClumps());
}
}

// This code is contributed by shivanisinghss2110

Javascript

<script>

    // Javascript program to calculate
    // the number of clumps in
    // an array

    // Function to count the number of
    // clumps in the given array arr[]
    function countClumps(arr, N)
    {

        // Initialise count of clumps as 0
        let clumps = 0;

        // Traverse the arr[]
        for (let i = 0; i < N - 1; i++) {

            let flag = 0;
            // Whenever a sequence of same
            // value is encountered
            while (arr[i] == arr[i + 1]) {
                flag = 1;
                i++;
            }

            if (flag)
                clumps++;
        }

        // Return the count of clumps
        return clumps;
    }

    // Given array
    let arr = [ 13, 15, 66, 66, 66, 37, 37, 8, 8, 11, 11 ];

    // length of the given array arr[]
    let N = arr.length;

    // Function Call
    document.write(countClumps(arr, N));

</script>

Output:

4

Time Complexity: O(N), where N is the number of elements in the given array. 
Auxiliary Space: O(1)