How to Find the Median of Sorted Vector in C++?

Last Updated : 12 Mar, 2024

In C++, vectors are dynamic arrays and the median is a middle value when data is sorted in ascending order. In this article, we will learn how to find the median of all elements in a sorted vector in C++.

Example

Input:
myVector = {10, 20, 30, 40, 50};

Output:
Median is 30

Finding Median of Sorted Vector in C++

To find the median of a sorted vector in C++, first check if the size of the vector is even or odd.

If the size is odd, the median is the element at the middle index.
If the size is even, the median is the average of the two middle elements.

C++ Program to Find the Median of Sorted Vector

The below example demonstrates how we can find the median of elements stored in a sorted vector in C++.

C++


                    // C++ Program to illustrate how to find the median of all
// elements in a sorted vector
#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

// Function to find the median of a sorted vector
int findMedian(vector<int>& vec)
{
    // Find the size of the vector
    int size = vec.size();

    if (size % 2 == 0) {
        // If the size is even
        return (vec[size / 2 - 1] + vec[size / 2]) / 2;
    }
    else {
        // If the size is odd
        return vec[size / 2];
    }
}

int main()
{

    // Intializing two vectors
    vector<int> vecOdd = { 10, 20, 30, 40, 50 };
    vector<int> vecEven = { 10, 20, 30, 40, 50, 60 };

    // Find the median of the odd vector
    int median1 = findMedian(vecOdd);
    cout << "Median of oddVec: " << median1 << endl;

    // Find the median of the even vector
    int median2 = findMedian(vecEven);
    cout << "Median of evenVec: " << median2 << endl;
    return 0;
}

Output

Median of oddVec: 30
Median of evenVec: 35

Time Complexity: O(1), as the vector is already sorted
Auxiliary Space: O(1)