Tính định thức ma trận

/************************Determinate of matrix******************/
 
#include "stdio.h"
#include "conio.h"
#include "stdlib.h"
#define N 10
 
#define SIGN(x) (x%2? -1 : 1)
 
int** allocArr(short szRow, short szCol);
void ImportData(int** Arr, int nRow, int nCol, char name);
int DetOfMatrix(int** Arr, int sz);
void FreeMem(int **Buff, int n);
 
void main()
{
 int iRow, iCol;
 int size;
 int** Arr;
 
 printf("\nsize of matrix: ");
 scanf("%d", &size);
 Arr = allocArr(size, size);
 ImportData(Arr, size, size, 'A');
 printf("det(A) = %d", DetOfMatrix(Arr, size));
 
 getch();
}
 
/*************************************************************
//Function : Import data for matrix
//Parameter: matrix, and the number of row and column and
//name matrix
//Return : void
*************************************************************/
void ImportData(int** Arr, int nRow, int nCol, char name)
{
 int iRow, iCol;
 for(iRow = 0; iRow < nRow; iRow++)
 for(iCol = 0; iCol < nCol; iCol++)
 {
 printf("\n%c[%d][%d] = ", name, iRow, iCol);
 scanf("%d", &Arr[iRow][iCol]);
 }
}
 
/************************************************************
*Function : calculate determinant of matrix nxn
*Parameter: matrix, and the number of row and column
*Return : void
************************************************************/
 
int DetOfMatrix(int** Arr, int sz)
{
 int i, j, k, p = 0;
 int det = 0;
 int m, n;
 int** subArr;
 if (sz < 2)
 {
 return -1;
 }
 if (sz == 2)
 {
 return (Arr[0][0]*Arr[1][1] - Arr[0][1]*Arr[1][0]);
 }
 else
 {
 if (!(subArr = allocArr(sz - 1, sz - 1)))
 {
 return -1;
 }
 for (i = 0; i < sz; i++)
 {
 m = n = 0;
 for (j = 1; j < sz; j++)
 {
 for (k = 0; k < sz; k++)
 {
 if (k != i)
 {
 subArr[m][n] = Arr[j][k]; 
 n++;
 if (n == sz-1)
 {
 m++;
 n = 0;
 }
 
 }
 }
 }
 det += SIGN(i)*Arr[0][i]*DetOfMatrix(subArr, sz - 1);
 }
 FreeMem(subArr, sz-1);
 return det;
 }
}
 
int** allocArr(short szRow, short szCol)
{
 int i;
 int **pArr;
 // Allocate memory for array
 pArr = (int**)malloc(szRow * sizeof(int *));
 if (!pArr)
 {
 return NULL;
 }
 for(i = 0; i < szRow; i++)
 {
 pArr[i] = (int*)malloc(szCol * sizeof(int));
 if (!pArr[i])
 {
 return NULL;
 }
 }
 return pArr;
}
 
/*************************************************************
*Function : free allocated memory
*Parameter: pointer to memory
*Return : void
*************************************************************/
void FreeMem(int **Buff, int n)
{
 int i, j;
 for (i = 0; i < n; i++)
 {
 if (Buff[i])
 {
 free(Buff[i]);
 Buff[i] = NULL;
 }
 }
 if (Buff)
 {
 free(Buff);
 } 
}