Cover Image for Remove Duplicates from Sorted Array in C++
93 views

Remove Duplicates from Sorted Array in C++

To remove duplicates from a sorted array in C++, you can implement a simple algorithm that iterates through the array and eliminates any duplicate elements in-place. Here’s an example of how to do this:

C++
#include <iostream>
#include <vector>

// Function to remove duplicates from a sorted array
int removeDuplicates(std::vector<int>& nums) {
    if (nums.empty()) {
        return 0; // Return 0 for an empty array
    }

    int uniqueCount = 1; // Initialize the count of unique elements to 1

    for (int i = 1; i < nums.size(); ++i) {
        // If the current element is different from the previous one, update it
        if (nums[i] != nums[i - 1]) {
            nums[uniqueCount] = nums[i];
            ++uniqueCount;
        }
    }

    return uniqueCount; // Return the count of unique elements
}

int main() {
    std::vector<int> nums = {1, 1, 2, 2, 2, 3, 4, 4, 5, 5, 5};

    int uniqueCount = removeDuplicates(nums);

    std::cout << "Unique Count: " << uniqueCount << std::endl;
    std::cout << "Unique Array: ";
    for (int i = 0; i < uniqueCount; ++i) {
        std::cout << nums[i] << " ";
    }
    std::cout << std::endl;

    return 0;
}

In this example:

  • We define a removeDuplicates function that takes a reference to a std::vector<int> as its parameter.
  • The function iterates through the sorted array and keeps track of a uniqueCount variable, which represents the count of unique elements encountered so far.
  • If the current element is different from the previous one, it is considered a unique element, and we update the array at the position uniqueCount with the current element.
  • After processing the entire array, the function returns the value of uniqueCount, representing the count of unique elements.
  • In the main function, we call removeDuplicates on a sorted vector of integers and print the count of unique elements as well as the unique elements themselves.

The result of running this program will be:

Unique Count: 5
Unique Array: 1 2 3 4 5 

The duplicate elements have been removed from the sorted array, and the unique elements are left in the array with the appropriate count.

YOU MAY ALSO LIKE...

The Tech Thunder

The Tech Thunder

The Tech Thunder


COMMENTS