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C++ Program to Compute Determinant of a Matrix



C++ Program to Compute Determinant of a Matrix

This is a C++ Program to compute the determinant of the given matrix.

    #include<conio.h>

    #include<iostream>

    #include<math.h>

    using namespace std;

    double d = 0;

    double det(int n, double mat[10][10]);

    double det(int n, double mat[10][10])

    {

        double submat[10][10];

        if (n == 2)

            return ((mat[0][0] * mat[1][1]) - (mat[1][0] * mat[0][1]));

        else

        {

            for (int c = 0; c < n; c++)

            {

                int subi = 0; //submatrix's i value

                for (int i = 1; i < n; i++)

                {

                    int subj = 0;

                    for (int j = 0; j < n; j++)

                    {

                        if (j == c)

                            continue;

                        submat[subi][subj] = mat[i][j];

                        subj++;

                    }

                    subi++;

                }

                d = d + (pow(-1, c) * mat[0][c] * det(n - 1, submat));

            }

        }

        return d;

    }

    int main(int argc, char **argv)

    {

        cout << "Enter the dimension of the matrix:\n";

        int n;

        cin >> n;

        double mat[10][10];

        cout << "Enter the elements of the matrix:\n";

        for (int i = 0; i < n; i++)

        {

            for (int j = 0; j < n; j++)

            {

                cin >> mat[j][i];

            }

        }

        cout << "The determinant of the given matrix is: " << det(n, mat);

    	return 0;

    }