How to calculate the sum of two matrices of order N x N with c plus plus

In this example, written in c++, the code shows how to perform the sum of two matrices of order N x N.

/**
Given two matrices of size n x n,
Calculate the matrix sum
*/

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>  

int main ()
{
    // Initialize random number generator
	srand(time(NULL));
	
    // Define the length of the array
    const int N = 5;

	// Define two matrices of dimension N x N
	int m1 [N][N];
	int m2 [N][N];

	// Define the matrix sum
	int sum [N][N];

	// Fill the matrices m1 and m2 with random integers
	for(int i=0; i<N; i++)
	{
		for(int j=0; j<N; j++)
		{ 
			m1[i][j] = (rand()%10)+1;
			m2[i][j] = (rand()%10)+1;
		}
	}

	// Showing the matrix m1
	printf("MATRIX M1\n");
	for(int i=0; i<N; i++)
	{
		for(int j=0; j<N; j++)
		{
			printf( "%d \t", m1[i][j]);
		}
		printf( "\n");
	}

	printf("\n");

	// Showing the matrix m2
	printf("MATRIX M2\n");
	for(int i=0; i<N; i++)
	{
		for(int j=0; j<N; j++)
		{
			printf( "%d \t", m2[i][j]);
		}
		printf( "\n");
	}

	// Calculating the matrix sum
	for(int i=0; i<N; i++)
	{
		for(int j=0; j<N; j++)
		{
			sum[i][j] = m1[i][j] + m2[i][j];
		}
	}

    printf("\n");

	// Showing the matrix sum
	printf("MATRIX SUM\n");
	for(int i=0; i<N; i++)
	{
		for(int j=0; j<N; j++)
		{
			printf( "%d \t", sum[i][j]);
		}
		printf( "\n");
	}

	return 0;
}

This is the result:

MATRIX M1
8     2     4     1      4    
8     2     1     7      2    
10   3     7     3      4    
2     5     2     3       3    
7     10   1     10    2    

MATRIX M2
9     10     4     2     8    
5     8       8     5     5    
5     5       1     1     8    
5     1       5     8     1    
3     10     5     7     2    

MATRIX SUM
17     12     8     3     12    
13     10     9     12     7    
15     8       8     4     12    
7       6       7     11     4    
10     20    6     17     4