Count Occurrences of Element in Sorted Array in DSA C++ - Build from Scratch

Count Occurrences of Element in Sorted Array

📖 Scenario: You have a sorted list of product IDs representing items sold in a store. You want to find out how many times a specific product ID appears in this list.

🎯 Goal: Build a program that counts how many times a given product ID appears in a sorted array of product IDs.

📋 What You'll Learn

Create an array called product_ids with the exact values: {101, 102, 102, 102, 103, 104, 104, 105}

Create an integer variable called target_id and set it to 102

Write a function called countOccurrences that takes the array product_ids, its size, and target_id as parameters and returns the count of target_id in the array

Print the count returned by countOccurrences

💡 Why This Matters

🌍 Real World

Counting how many times a product appears in sales data helps stores understand product popularity and manage inventory.

💼 Career

This skill is useful for software developers working with data analysis, inventory management systems, and any application needing frequency counts in sorted data.

1

Create the sorted array of product IDs

Create an integer array called product_ids with these exact values: {101, 102, 102, 102, 103, 104, 104, 105}

DSA C++

// Your code here

Hint

Use C++ array syntax to create product_ids with the given values.

2

Set the target product ID to count

Create an integer variable called target_id and set it to 102

DSA C++

int product_ids[] = {101, 102, 102, 102, 103, 104, 104, 105};
// Your code here

Hint

Declare target_id as an integer and assign it the value 102.

3

Write the function to count occurrences

Write a function called countOccurrences that takes three parameters: an integer array called arr, an integer size, and an integer target. The function should return the number of times target appears in arr. Use a for loop with variable i to iterate from 0 to size - 1 and count matches.

DSA C++

int product_ids[] = {101, 102, 102, 102, 103, 104, 104, 105};
int target_id = 102;

// Your code here

Hint

Use a loop to check each element and increase count when you find target.

4

Print the count of the target product ID

Print the result of calling countOccurrences with product_ids, the size of product_ids (which is 8), and target_id. Use std::cout to display the count.

DSA C++

int product_ids[] = {101, 102, 102, 102, 103, 104, 104, 105};
int target_id = 102;

int countOccurrences(int arr[], int size, int target) {
    int count = 0;
    for (int i = 0; i < size; i++) {
        if (arr[i] == target) {
            count++;
        }
    }
    return count;
}

// Your code here

Hint

Use std::cout to print the count returned by countOccurrences.