Find the Median


Problem Statement :


The median of a list of numbers is essentially its middle element after sorting. The same number of elements occur after it as before. Given a list of numbers with an odd number of elements, find the median?


Function Description

Complete the findMedian function in the editor below.

findMedian has the following parameter(s):

int arr[n]: an unsorted array of integers
Returns

int: the median of the array

Input Format

The first line contains the integer n, the size of arr.
The second line contains n space-separated integers arr[i]


Solution :



title-img 


                            Solution in C :

In  C++  :





#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {

    int n, *arr;
    cin>>n;
    arr = new int[n];
    for (int i = 0 ; i < n ; i++) cin>>arr[i];
    sort(arr,arr+n);
    if (n%2 == 1) cout<<arr[(n-1)/2]<<endl;
    else cout<<(arr[n/2 - 1]+arr[n/2])/2<<endl;
    return 0;
}









In   Java  :






import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static int quickSort(int[] a, int p, int r,int index)
    {
        if(p==r)
            return a[p];
        if(p<r)
        {
            int q=partition(a,p,r);
            if(q==index)
                return a[q];
            else if(q>index)
                return quickSort(a,p,q-1,index);
            else
                return quickSort(a,q+1,r,index);
        }
        
        return 0;
    }

    private static int partition(int[] a, int p, int r) {

        int x = a[r];
        int i = p-1 ;
        int j = p ;
        
        for(;j<r;++j)
        {
              if(a[j]<=x)  
              {
                  ++i;
                  int temp = a[i];
                  a[i]=a[j];
                  a[j]=temp;
              }
        }
        
        a[r]=a[i+1];
        a[i+1]=x;
        
        return i+1;
    }
    
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        
        int N = sc.nextInt();
        int[] arr = new int[N];
        
        for(int i=0;i<N;++i)
            arr[i]=sc.nextInt();
        
        System.out.println(quickSort(arr, 0, N-1,N/2));
    }
}










In  C  :








#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>

int compare (const void * a, const void * b)
{
  return ( *(int*)a - *(int*)b );
}

/* Tail starts here */
int main() 
{
   int _ar_size;
   scanf("%d", &_ar_size);
   int _ar[_ar_size], _ar_i;
   for(_ar_i = 0; _ar_i < _ar_size; _ar_i++) 
   { 
     scanf("%d", &_ar[_ar_i]);  
   }
   
   qsort (_ar, _ar_size, sizeof(int), compare);
   printf("%d",_ar[_ar_size/2]);
   
   return 0;
}










In   Python3 :








import math
def main():
    testcase = int(input())
    med = [int(i) for i in input().split()]
    print(findmed(med))
    
def findmed(med):
    med.sort()
    if(len(med)%2 == 1):
        return med[int(len(med)/2)]
    else:
        return (med[math.floor(len(med)/2)+math.ceil(len(med)/2)])/2
main()








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