Sum of middle row and column in Matrix

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Given an integer matrix of odd dimensions (3 * 3, 5 * 5). then the task is to find the sum of the middle row & column elements.

Examples:

Input :  2 5 7
         3 7 2
         5 6 9
Output : Sum of middle row = 12
         Sum of middle column = 18

Input :  1 3 5 6 7
         3 5 3 2 1
         1 2 3 4 5
         7 9 2 1 6
         9 1 5 3 2
Output : Sum of middle row = 15
         Sum of middle column = 18

Implementation:

CPP

// C++ program to find sum of 
// middle row and column in matrix
#include <iostream>
using namespace std;
const int MAX = 100;
 
void middlesum(int mat[][MAX], int n)
{
 
    int  row_sum = 0, col_sum = 0;
     
    //loop for sum of row
    for (int i = 0; i < n; i++)
        row_sum += mat[n / 2][i];
     
    cout << "Sum of middle row = "
                    << row_sum<<endl;
     
    //loop for sum of column
    for (int i = 0; i < n; i++)
        col_sum += mat[i][n / 2];
     
    cout << "Sum of middle column = "
                            << col_sum;
}
 
// Driver function
int main()
{
    int mat[][MAX] = {{2, 5, 7},
                     {3, 7, 2}, 
                     {5, 6, 9}};
     
    middlesum(mat, 3);
    
    return 0;
}

Java

// java  program to find sum of 
// middle row and column in matrix
 
import java.io.*;
 
class GFG {
     
 
static  int MAX = 100;
 
 static void middlesum(int mat[][], int n)
{
 
    int row_sum = 0, col_sum = 0;
     
    // loop for sum of row
    for (int i = 0; i < n; i++)
        row_sum += mat[n / 2][i];
     
    System.out.println ( "Sum of middle row = "
                  + row_sum);
     
    // loop for sum of column
    for (int i = 0; i < n; i++)
        col_sum += mat[i][n / 2];
     
    System.out.println ( "Sum of middle column = "
                 + col_sum);
}
 
// Driver function
    public static void main (String[] args) {
        int mat[][] = {{2, 5, 7},
                    {3, 7, 2}, 
                    {5, 6, 9}};
     
        middlesum(mat, 3);
     
    }
}
 
// This code is contributed by vt_m.

Python3

# Python program to find sum of 
# middle row and column in matrix
 
  
def middlesum(mat,n):
  
    row_sum = 0
    col_sum = 0
      
    # loop for sum of row
    for i in range(n):
        row_sum += mat[n // 2][i]
      
    print("Sum of middle row = ",
                     row_sum)
      
    # loop for sum of column
    for i in range(n):
        col_sum += mat[i][n // 2]
      
    print("Sum of middle column = ",
                            col_sum)
 
# Driver code
mat= [[2, 5, 7],
     [3, 7, 2], 
     [5, 6, 9]]
      
middlesum(mat, 3)
 
# This code is contributed
# by Anant Agarwal.

C#

// C# program to find sum of 
// middle row and column in matrix
using System;
 
class GFG {
     
 
    //static int MAX = 100;
     
    static void middlesum(int [,]mat, int n)
    {
     
        int row_sum = 0, col_sum = 0;
         
        // loop for sum of row
        for (int i = 0; i < n; i++)
            row_sum += mat[n / 2, i];
         
        Console.WriteLine ( "Sum of middle row = "
                    + row_sum);
         
        // loop for sum of column
        for (int i = 0; i < n; i++)
            col_sum += mat[i, n / 2];
         
        Console.WriteLine ( "Sum of middle column = "
                            + col_sum);
    }
 
    // Driver function
    public static void Main () {
        int [,]mat = {{2, 5, 7},
                    {3, 7, 2}, 
                    {5, 6, 9}};
     
        middlesum(mat, 3);
     
    }
}
 
// This code is contributed by vt_m.

PHP

<?php
// PHP program to find sum of 
// middle row and column in matrix
 
function middlesum( $mat,  $n)
{
 
     $row_sum = 0; $col_sum = 0;
     
    //loop for sum of row
    for ( $i = 0; $i < $n; $i++)
        $row_sum += $mat[$n / 2][$i];
     
    echo "Sum of middle row = "
                    , $row_sum,"\n";
     
    //loop for sum of column
    for ( $i = 0; $i < $n; $i++)
        $col_sum += $mat[$i][$n / 2];
     
    echo "Sum of middle column = "
                            , $col_sum;
}
 
// Driver function
 
     $mat = array(array(2, 5, 7),
                 array(3, 7, 2), 
                array(5, 6, 9));
     
    middlesum($mat, 3);
     
// This code is contributed by anuj_67.
?>

Javascript

<script>
 
// Javascript  program to find sum of 
// middle row and column in matrix    
var MAX = 100;
 
    function middlesum(mat , n)
    {
 
        var row_sum = 0, col_sum = 0;
 
        // loop for sum of row
        for (i = 0; i < n; i++)
            row_sum += mat[parseInt(n / 2)][i];
 
        document.write(
        "Sum of middle row = " + row_sum+"<br/>"
        );
 
        // loop for sum of column
        for (i = 0; i < n; i++)
            col_sum += mat[i][parseInt(n / 2)];
 
        document.write(
        "Sum of middle column = " + col_sum
        );
    }
 
    // Driver function
     
        var mat = [ [ 2, 5, 7 ], 
                    [ 3, 7, 2 ],
                    [ 5, 6, 9 ] ];
 
        middlesum(mat, 3);
 
// This code contributed by aashish1995
 
</script>

Output

Sum of middle row = 12
Sum of middle column = 18

Time Complexity : O(n)
Auxiliary Space: O(1) using constant space to initialize row_sum and col_sum variables, since no extra space has been taken.

Using Stl:

Here we use the accumulate function to do it.

For JavaScript:

Here we use the reduce function to do it.

C++

#include <iostream>
#include<bits/stdc++.h>
using namespace std;
 
int main() {
    vector<vector<int>>v{{2, 5, 7},
                         {3, 7, 2},
                         {5, 6, 9}};
    int n=v.size();
    cout<<"The sum of all the element in middle row : "<<endl;
    cout<<accumulate(v[n/2].begin(),v[n/2].end(),0)<<endl;
    for(int i=0;i<n;i++)
        for(int j=i+1;j<n;j++)
            swap(v[i][j],v[j][i]);
   cout<<"The sum of all the element in middle column : "<<endl;
   cout<<accumulate(v[n/2].begin(),v[n/2].end(),0);
    return 0;
}

Java

import java.util.Arrays;
 
public class Main {
    public static void main(String[] args) {
        int[][] v = {{2, 5, 7},
                     {3, 7, 2},
                     {5, 6, 9}};
        int n = v.length;
        System.out.println("The sum of all the element in middle row : ");
        System.out.println(Arrays.stream(v[n/2]).sum());
        for(int i = 0; i < n; i++)
            for(int j = i + 1; j < n; j++) {
                int temp = v[i][j];
                v[i][j] = v[j][i];
                v[j][i] = temp;
            }
       System.out.println("The sum of all the element in middle column : ");
       System.out.println(Arrays.stream(v[n/2]).sum());
    }
}

Python3

# Python code to implement the above approach
v = [[2, 5, 7],
     [3, 7, 2],
     [5, 6, 9]]
n = len(v)
 
print("The sum of all the element in middle row : ")
print(sum(v[n//2]))
 
for i in range(n):
    for j in range(i+1,n):
        v[i][j],v[j][i] = v[j][i],v[i][j]
         
print("The sum of all the element in middle column : ")
print(sum(v[n//2]))

Javascript

// JavaScript code to implement the above approach
var v = [[2, 5, 7],
         [3, 7, 2],
         [5, 6, 9]];
var n = v.length;
 
console.log("The sum of all the element in middle row : ");
console.log(v[Math.floor(n/2)].reduce((a,b)=>a+b,0));
 
for(var i=0;i<n;i++)
    for(var j=i+1;j<n;j++)
        [v[i][j],v[j][i]] = [v[j][i],v[i][j]];
         
console.log("The sum of all the element in middle column : ");
console.log(v[Math.floor(n/2)].reduce((a,b)=>a+b,0));
 
// contributed by rishabh

C#

using System;
using System.Collections.Generic;
using System.Linq;
 
class Program {
    static void Main(string[] args) {
        List<List<int>> v = new List<List<int>> {
            new List<int> { 2, 5, 7 },
            new List<int> { 3, 7, 2 },
            new List<int> { 5, 6, 9 }
        };
        int n = v.Count;
        Console.WriteLine("The sum of all the element in middle row : ");
        Console.WriteLine(v[n / 2].Sum());
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                int temp = v[i][j];
                v[i][j] = v[j][i];
                v[j][i] = temp;
            }
        }
        Console.WriteLine("The sum of all the element in middle column : ");
        Console.WriteLine(v[n / 2].Sum());
    }
}
// This code is contributed by user_dtewbxkn77n

Output

The sum of all the element in middle row : 
12
The sum of all the element in middle column : 
18

The accumulated value of f applications. Complexity: O(n×k), where n is the distance from first to last , O(k) is complexity of f function.

Time Complexity: O(n*k).
Auxiliary Space : O(k)

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Last Updated : 25 Mar, 2023