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Check if row-major order path of Matrix is palindrome or not

Given a matrix mat[][], the task is to check if the row-major order path of the matrix is a palindrome or not.

Examples: 

Input: mat[][] = {{1, 2, 3}, {4, 5, 4}, {3, 2, 1}} 
Output: YES 
Explanation: 
Row-major order traversal of matrix is – 
1 => 2 => 3 => 4 => 5 => 4 => 3 => 2 => 1 
Reverse row-major order traversal of matrix is – 
1 => 2 => 3 => 4 => 5 => 4 => 3 => 2 => 1 
Since, the reverse and forward traversal of matrix is same. 
Therefore, it is a palindrome.

Input: mat[][] = {{1, 2}, {2, 3}} 
Output: NO  

Approach: The idea is to traverse the half matrix and check its opposite half elements are the same or not at the same time. That is for the index of i and j, check that and . If for any index there is a mismatch, print NO.

Below is the implementation of the above approach: 

// C++ implementation to check if
// row-major order traversal of
// matrix is palindrome or not
 
#include <bits/stdc++.h>
using namespace std;
 
// Function to check if row-major order
// traversal of the matrix is palindrome
bool isPal(int a[3][3], int n, int m)
{
    // Loop to check if the matrix is
    // matrix is palindrome or not
    for (int i = 0; i < n / 2; i++) {
        for (int j = 0; j < m - 1; j++) {
            if (a[i][j] != a[n - 1 - i][m - 1 - j])
                return false;
        }
    }
    return true;
}
 
// Driver Code
int main()
{
    int n = 3, m = 3;
    int a[3][3] = { { 1, 2, 3 },
                    { 4, 5, 4 },
                    { 3, 2, 1 } };
    if (isPal(a, n, m)) {
        cout << "YES" << endl;
    }
    else {
        cout << "NO" << endl;
    }
}

                    
// Java implementation to check if
// row-major order traversal of
// matrix is palindrome or not
import java.util.*;
 
class GFG{
 
// Function to check if row-major order
// traversal of the matrix is palindrome
static boolean isPal(int a[][], int n, int m)
{
     
    // Loop to check if the matrix is
    // matrix is palindrome or not
    for(int i = 0; i < n / 2; i++)
    {
       for(int j = 0; j < m - 1; j++)
       {
          if (a[i][j] != a[n - 1 - i][m - 1 - j])
              return false;
       }
    }
    return true;
}
 
// Driver Code
public static void main(String[] args)
{
    int n = 3, m = 3;
    int a[][] = { { 1, 2, 3 },
                  { 4, 5, 4 },
                  { 3, 2, 1 } };
                   
    if (isPal(a, n, m))
    {
        System.out.print("YES" + "\n");
    }
    else
    {
        System.out.print("NO" + "\n");
    }
}
}
 
// This code is contributed by gauravrajput1

                    
# Python3 implementation to check if
# row-major order traversal of
# matrix is palindrome or not
 
# Function to check if row-major order
# traversal of the matrix is palindrome
def isPal(a, n, m):
     
    # Loop to check if the matrix is
    # matrix is palindrome or not
    for i in range(0, n // 2):
        for j in range(0, m - 1):
            if (a[i][j] != a[n - 1 - i][m - 1 - j]):
                return False;
 
    return True;
 
# Driver Code
if __name__ == '__main__':
    n = 3;
    m = 3;
    a = [[1, 2, 3], [4, 5, 4], [3, 2, 1]];
 
    if (isPal(a, n, m)):
        print("YES");
    else:
        print("NO");
 
# This code is contributed by Princi Singh

                    
// C# implementation to check if
// row-major order traversal of
// matrix is palindrome or not
using System;
 
class GFG{
 
// Function to check if row-major order
// traversal of the matrix is palindrome
static bool isPal(int[,]a, int n, int m)
{
     
    // Loop to check if the matrix is
    // matrix is palindrome or not
    for(int i = 0; i < n / 2; i++)
    {
       for(int j = 0; j < m - 1; j++)
       {
           if (a[i, j] != a[n - 1 - i,
                            m - 1 - j])
               return false;
       }
    }
    return true;
}
 
// Driver Code
public static void Main(String[] args)
{
    int n = 3, m = 3;
    int[,]a = { { 1, 2, 3 },
                { 4, 5, 4 },
                { 3, 2, 1 } };
                     
    if (isPal(a, n, m))
    {
        Console.Write("YES" + "\n");
    }
    else
    {
        Console.Write("NO" + "\n");
    }
}
}
 
// This code is contributed by gauravrajput1

                    
<script>
 
// JavaScript implementation to check if
// row-major order traversal of
// matrix is palindrome or not
 
// Function to check if row-major order
// traversal of the matrix is palindrome
function isPal(a, n, m)
{
     
    // Loop to check if the matrix is
    // matrix is palindrome or not
    for(let i = 0; i < n / 2; i++)
    {
       for(let j = 0; j < m - 1; j++)
       {
          if (a[i][j] != a[n - 1 - i][m - 1 - j])
              return false;
       }
    }
    return true;
}
   
// Driver Code
let n = 3, m = 3;
let a = [ [ 1, 2, 3 ],
          [ 4, 5, 4 ],
          [ 3, 2, 1 ] ];
           
if (isPal(a, n, m))
{
    document.write("YES" + "\n");
}
else
{
    document.write("NO" + "\n");
}
 
// This code is contributed by susmitakundugoaldanga
          
</script>

                    

Output
YES

Time complexity: O(n*m) where n and m are no of rows and columns of a given input matrix

Auxiliary Space: O(n*m) 


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