Program to find Normal and Trace of a matrix

Given a 2D matrix, the task is to find Trace and Normal of matrix.

Normal of a matrix is defined as square root of sum of squares of matrix elements.

Trace of a n x n square matrix is sum of diagonal elements.

Examples:

Input : mat[][] = {{7, 8, 9},
                   {6, 1, 2},
                   {5, 4, 3}};
Output : Normal = 16  
         Trace  = 11
Explanation : 
Normal = sqrt(7*7+ 8*8 + 9*9 + 6*6 +
              1*1 + 2*2 + 5*5 + 4*4 + 3*3)   
       = 16
Trace  = 7+1+3 = 11

Input :mat[][] = {{1, 2, 3},
                  {6, 4, 5},
                  {2, 1, 3}};
Output : Normal = 10  
         Trace = 8
Explanation : 
Normal = sqrt(1*1 +2*2 + 3*3 + 6*6 + 4*4 + 
             5*5 + 2*2 + 1*1 + 3*3)   
Trace = 8(1+4+3)

Untitled

// C++ program to find trace and normal
// of given matrix
#include<bits/stdc++.h>
using namespace std;

// Size of given matrix
const int MAX = 100;

// Returns Normal of a matrix of size n x n
int findNormal(int mat[][MAX], int n)
{
    int sum = 0;
    for (int i=0; i<n; i++)
        for (int j=0; j<n; j++)
            sum += mat[i][j]*mat[i][j];
    return sqrt(sum);
}

// Returns trace of a matrix of size n x n
int findTrace(int mat[][MAX], int n)
{
    int sum = 0;
    for (int i=0; i<n; i++)
         sum += mat[i][i];
    return sum;
}

// Driven source
int main()
{
    int mat[][MAX] = {{1, 1, 1, 1, 1},
        {2, 2, 2, 2, 2},
        {3, 3, 3, 3, 3},
        {4, 4, 4, 4, 4},
        {5, 5, 5, 5, 5},
    };
    cout << "Trace of Matrix = "
         << findTrace(mat, 5) << endl;
    cout << "Normal of Matrix = "
         << findNormal(mat, 5) << endl;
    return 0;
}

Output:

Trace of matrix = 15
Normal of matrix = 285   

Time Complexity : O(n*n)
Space Complexity : O(1)

References:
https://en.wikipedia.org/wiki/Trace_(linear_algebra)

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