행렬식 값 구하기 (귀속)

/*
#include 
#include 
#define N 100
#define LIM -100000000
float det(float a[N][N],int n){
    if(n==1)
        return a[0][0];
    if(n==2)
        return a[0][0]*a[1][1]-a[0][1]*a[1][0];// the base situation
    else{
        int j,i,flag=1;
        float ret=0;
        for(j=0;j*/

#include 
#include 
 
#define  CONST 1e-6
#define  SIZE 20
 
void InputMatrix (double a[][SIZE], int n);
double DeterminantValue(double a[][SIZE], int n);
void SubMatrix(double a[][SIZE], double b[][SIZE], int n, int row, int col);
void PrintMatrix(double a[][SIZE], int n);
int main(void)
{
    double  a[SIZE][SIZE];
    int     n;
    double  result;
    printf("Please enter matrix size n(1<=n", SIZE);
    scanf("%d", &n);
    printf("Please input matrix line by line:
");
    InputMatrix(a, n);
    printf("matrix a:
");
    PrintMatrix(a, n);
    printf("
");
    result = DeterminantValue(a, n);
    printf("result = %f
", result);
    return 0;
}
//   ：  n×n 
void InputMatrix (double a[][SIZE], int n)
{
    int i, j;
    for (i = 0; i < n; i++)
    {
        for (j = 0; j < n; j++)
        {
            scanf("%lf", &a[i][j]);
        }
    }
}
//   ：  n×n 
double DeterminantValue(double a[][SIZE], int n)
{
    int    i = 0, j = 0;
    double temp, result, b[SIZE][SIZE];
    if (n == 1)
    {
        result = a[0][0];
    }
    else if (n == 2)
    {
        result = a[0][0] * a[1][1] - a[0][1] * a[1][0];
    }
    else
    {
        result = 0.0;
        for (j = 0; j < n; j++)// 
        {
            SubMatrix(a, b, n, i, j);//the key
            printf("Submatrix:
");
            PrintMatrix(b, n - 1);
            temp = DeterminantValue(b, n - 1);        // 
            result += pow(-1, i + j) * a[0][j] * temp;
            printf("DValue of the Submatrix is %6.1f
", temp);
        }
    }
    return result;
}
//   ：  n×n a row col (n-1)×(n-1) b
void SubMatrix(double a[][SIZE], double b[][SIZE], int n, int row,
               int col)
{
    int i, j, ii = 0, jj = 0;
    for (i = 0; i < n; i++)
    {
        jj = 0;// 0
        for (j = 0; j < n; j++)// j 
        {
            if (i != row && j != col)// i j 
            {
                b[ii][jj] = a[i][j];
                jj++;
            }
        }
        if (i != row && j != col)// 
        {
            ii++;////////////////////////////////////////////////////////
        }        /////// i!=row&&... row,col /////////
    }            ////////////////////////////////////////////////////////
}
//   ：  n×n 
void PrintMatrix(double a[][SIZE], int n)
{
    int i, j;
    for (i = 0; i < n; i++)
    {
        for (j = 0; j < n; j++)
        {
            printf("%6.1f\t", a[i][j]);
        }
        printf("
");
    }
}