Find maximum element of each row in a matrix

Given a matrix, the task is to find the maximum element of each row.

Examples:

Input :  [1, 2, 3]
         [1, 4, 9]
         [76, 34, 21]

Output :
3
9
76

Input : [1, 2, 3, 21]
        [12, 1, 65, 9]
        [1, 56, 34, 2]
Output :
21
65
56

Approach : Approach is very simple. The idea is to run the loop for no_of_rows. Check each element inside the row and find for the maximum element. Finally, print the element. 

Implementation:

C++

#include<bits/stdc++.h>
using namespace std;

const int N = 4;

void printArray(int result[], int no_of_rows) {
    for (int i = 0; i < no_of_rows; i++) {
        cout<< result[i]<<"\n";
    }
}

void maxelement(int no_of_rows, int arr[][N]) {
    int result[no_of_rows];
    for (int i = 0; i < no_of_rows; i++) {
        int max = *max_element(arr[i], arr[i]+N);
        result[i] = max;
    }
    printArray(result,no_of_rows);
}

int main() {
    int arr[][N] = { {3, 4, 1, 8},
                    {1, 4, 9, 11},
                    {76, 34, 21, 1},
                    {2, 1, 4, 5} };
    maxelement(4, arr);
    return 0;
}

Java

// Java program to find maximum
// element of each row in a matrix
public class GFG{

    // Function to get max element
    public static void maxelement(int no_of_rows, int[][] arr) {
        int i = 0;

        // Initialize max to 0 at beginning
        // of finding max element of each row
        int max = 0;
        int[] result = new int[no_of_rows];
        while (i < no_of_rows) {
            for (int j = 0; j < arr[i].length; j++) {
                if (arr[i][j] > max) {
                    max = arr[i][j];
                }
            }
            result[i] = max;
            max =0;
            i++;

        }
        printArray(result);

    }

    // Print array element
    private static void printArray(int[] result) {
        for (int i =0; i<result.length;i++) {
            System.out.println(result[i]);
        }

    }

    // Driver code
    public static void main(String[] args) {
        int[][] arr = new int[][] { {3, 4, 1, 8},
                                    {1, 4, 9, 11},
                                    {76, 34, 21, 1},
                                   {2, 1, 4, 5} };
       // Calling the function
        maxelement(4, arr);
    }
}

Python

# Python program to find maximum
# element of each row in a matrix

# importing numpy
import numpy

# Function to get max element
def maxelement(arr):

    # get number of rows and columns
    no_of_rows = len(arr)
    no_of_column = len(arr[0])

    for i in range(no_of_rows):

        # Initialize max1 to 0 at beginning
        # of finding max element of each row
        max1 = 0
        for j in range(no_of_column):
            if arr[i][j] > max1 :
                max1 = arr[i][j]

        # print maximum element of each row
        print(max1)

# Driver Code
arr = [[3, 4, 1, 8],
       [1, 4, 9, 11],
       [76, 34, 21, 1],
       [2, 1, 4, 5]]

# Calling the function
maxelement(arr)

C#

// C# program to find maximum
// element of each row in a matrix
using System;

class GFG
{

// Function to get max element
public static void maxelement(int no_of_rows,
                              int[][] arr)
{
    int i = 0;

    // Initialize max to 0 at beginning
    // of finding max element of each row
    int max = 0;
    int[] result = new int[no_of_rows];
    while (i < no_of_rows)
    {
        for (int j = 0;
                 j < arr[i].Length; j++)
        {
            if (arr[i][j] > max)
            {
                max = arr[i][j];
            }
        }
        result[i] = max;
        max = 0;
        i++;

    }
    printArray(result);

}

// Print array element
private static void printArray(int[] result)
{
    for (int i = 0; i < result.Length;i++)
    {
        Console.WriteLine(result[i]);
    }

}

// Driver code
public static void Main(string[] args)
{
    int[][] arr = new int[][]
    {
        new int[] {3, 4, 1, 8},
        new int[] {1, 4, 9, 11},
        new int[] {76, 34, 21, 1},
        new int[] {2, 1, 4, 5}
    };

    // Calling the function
    maxelement(4, arr);
}
}

// This code is contributed by Shrikant13

PHP

<?php
// PHP program to find maximum
// element of each row in a matrix
$N = 4;


// Print array element
function printArray($result, $no_of_rows)
{
    for ($i = 0; $i < $no_of_rows; $i++)
    {
        echo $result[$i]."\n";
    }

}

// Function to get max element
function maxelement($no_of_rows, $arr)
{
    global $N;
    $i = 0;

    // Initialize max to 0 at beginning
    // of finding max element of each row
    $max = 0;
    $result=array_fill(0,$no_of_rows,0);
    while ($i < $no_of_rows)
    {
        for ($j = 0; $j < $N; $j++)
        {
            if ($arr[$i][$j] > $max)
            {
                $max = $arr[$i][$j];
            }
        }
        $result[$i] = $max;
        $max = 0;
        $i++;

    }
    printArray($result,$no_of_rows);

}

// Driver code
$arr = array(array(3, 4, 1, 8),
                array(1, 4, 9, 11),
                array(76, 34, 21, 1),
                array(2, 1, 4, 5));
// Calling the function
maxelement(4, $arr);

// This code is contributed by mits
?>

Javascript

<script>
// javascript program to find maximum
// element of each row in a matrix
// Function to get max element
function maxelement(no_of_rows, arr)
{
    var i = 0;

    // Initialize max to 0 at beginning
    // of finding max element of each row
    var max = 0;
    var result = Array.from({length: no_of_rows}, (_, i) => 0);
    while (i < no_of_rows)
    {
        for (var j = 0; j < arr[i].length; j++)
        {
            if (arr[i][j] > max)
            {
                max = arr[i][j];
            }
        }
        result[i] = max;
        max = 0;
        i++;

    }
    printArray(result);

}

// Print array element
function printArray(result)
{
    for (var i = 0; i < result.length; i++)
    {
        document.write(result[i]+"<br>");
    }

}

// Driver code
    var arr = [[3, 4, 1, 8],
    [ 1, 4, 9, 11],
    [ 76, 34, 21, 1],
   [ 2, 1, 4, 5] ];

// Calling the function
maxelement(4, arr);

// This code is contributed by 29AjayKumar
</script>

Output

8
11
76
5

Complexity Analysis:

• Time Complexity: O(n*m) (where, n refers to no. of rows and m refers to no. of columns)
• Auxiliary Space: O(n) (where, n refers to no. of rows)