solve using c/c++ or matlab //this code could be modified to solve it #include <

Question

solve using c/c++ or matlab

//this code could be modified to solve it

#include <stdlib.h>
#include <math.h>
#include <stdio.h>



//solve the linear system of equations A * X = rhs by using the Gauss elimination technique
// A, rhs, and n are input variables
// n is the number of equations in the system
// X is the output vector

void Solve(double **A, double *rhs, double *X, int n)
{
    double **w = new double*[n];
    for (int i = 0; i < n; i++) w[i] = new double[n];
    int **index = new int*[n];
    for (int i = 0; i < n; i++) index[i] = new int[3];

    int nv  = 1;
    int irow = 0;
    int icol = 0;
    double pivot;
    
    for (int i = 0; i < n; i++){
        w[i][0] = rhs[i];
        index[i][2] = 0;
    }

    double determ = 1;
    for (int i = 0; i < n; i++){
        double big = 0;
        for (int j = 0; j < n; j++){
            if (index[j][2] != 1)
                for (int k = 0; k < n; k++)
                {
                    if (index[k][2] > 1)
                    {
                        printf("Error at Gauss-Jordan: Matrix is singular ");
                        exit(1);
                    }
                    if (index[k][2] < 1)
                        if (fabs(A[j][k]) > big)
                        {
                            irow = j;
                            icol = k;
                            big = fabs(A[j][k]);
                        }
                }
        }

        index[icol][2] += 1;
        index[icol][0] = irow;
        index[icol][1] = icol;

        if (irow != icol)
        {
            determ = -determ;
            for (int l = 0; l < n; l++)
            {
                double temp = A[irow][l];
                A[irow][l] = A[icol][l];
                A[icol][l] = temp;
            }
            if (nv > 0)
                for (int l = 0; l < nv; l++)
                {
                    double temp = w[irow][l];
                    w[irow][l] = w[icol][l];
                    w[icol][l] = temp;
                }
        }

        pivot = A[icol][icol];
        determ *= pivot;
        A[icol][icol] = 1;

        for (int l = 0; l < n; l++)
            A[icol][l] /= pivot;
        if (nv != 0)
            for (int l = 0; l < nv; l++)
                w[icol][l] /= pivot;
        for (int l1 = 0; l1 < n; l1++){
            if (l1 != icol)
            {
                double t = A[l1][icol];
                A[l1][icol] = 0;
                for (int l = 0; l < n; l++)
                    A[l1][l] -= A[icol][l]*t;
                if (nv != 0)
                    for (int l = 0; l < nv; l++)
                        w[l1][l] -= w[icol][l]*t;
            }
        }
    }


    for (int i = 0; i < n; i++){
        int l = n-i-1;
        if (index[l][0] != index[l][1]){
            irow = index[l][0];
            icol = index [l][1];
            for (int k = 0; k < n; k++)
            {
                double temp = A[k][irow];
                A[k][irow] = A[k][icol];
                A[k][icol] = temp;
            }
        }
    }

    for (int k = 0; k < n; k++)
        if (index[k][2] != 1){
            printf("Error at Gauss-Jordan: Matrix is singular ");
            exit(1);
        }

    for (int i = 0; i < n; i++)
        X[i] = w[i][0];

    for (int i = 0; i < n; i++) delete [](w[i]);
    for (int i = 0; i < n; i++) delete [](index[i]);
    delete []w;
    delete []index;

}


/////////////////////////////////////////////////////////////////////////
// MAIN PROGRAM
/////////////////////////////////////////////////////////////////////////

//Solve the following system of equations
//       x + 2*y + 3*z =  1
//     3*x + 4*y + 5*z =  2
//     5*x + 6*y + 7*z =  3
int main()
{
    int n = 3;

    //make some memory allocations
    double **A = new double*[n];
    for (int i = 0; i < n; i++) A[i] = new double[n];
    double *rhs = new double[n];
    double *res = new double[n];

    //set the matrix
    for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
        A[i][j] = i+2*j+1;

    //set the right-hand-side
    for (int i = 0; i < n; i++)
        rhs[i] = i;

    //call function 'Solve' to solve the equations
    Solve (A,rhs,res, n);

    //print the result on the screen
    for (int i = 0; i < n; i++)
        printf("res[%d] = %e ", i,res[i]);

    //delete the memory allocated at the beginning
    for (int i = 0; i < n; i++) delete [](A[i]);
    delete []A;
    delete []rhs;
    delete []res;

    return 0;
}

Solve the following system of equations by using linear solver(variable x describe the electronic potential in p-n junction an applied voltage of approximately 3 V)

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