89 lines
1.9 KiB
C
89 lines
1.9 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
|
|
int m,n; // original matrix dimensions
|
|
|
|
int det(int B[m][n]);
|
|
|
|
int main() {
|
|
int determinant;
|
|
register int row,column;
|
|
|
|
printf("Enter rows and columns\n");
|
|
scanf("%d%d",&m,&n);
|
|
|
|
int A[m][n];
|
|
|
|
printf("Enter matrix elements\n");
|
|
|
|
for(row = 0; row < m; row++)
|
|
for(column = 0; column < n; column++)
|
|
scanf("%d",&A[row][column]);
|
|
|
|
determinant = det(A);
|
|
|
|
printf("determinant = %d \n",determinant);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int det(int B[m][n]) {
|
|
int row_size = m;
|
|
int column_size = n;
|
|
|
|
if (row_size != column_size) {
|
|
printf("DimensionError: Operation Not Permitted \n");
|
|
exit(1);
|
|
}
|
|
|
|
else if (row_size == 1)
|
|
return (B[0][0]);
|
|
|
|
else if (row_size == 2)
|
|
return (B[0][0]*B[1][1] - B[1][0]*B[0][1]);
|
|
|
|
else {
|
|
int minor[row_size-1][column_size-1];
|
|
int row_minor, column_minor;
|
|
int firstrow_columnindex;
|
|
int sum = 0;
|
|
|
|
register int row,column;
|
|
|
|
// exclude first row and current column
|
|
for(firstrow_columnindex = 0; firstrow_columnindex < row_size;
|
|
firstrow_columnindex++) {
|
|
|
|
row_minor = 0;
|
|
|
|
for(row = 1; row < row_size; row++) {
|
|
|
|
column_minor = 0;
|
|
|
|
for(column = 0; column < column_size; column++) {
|
|
if (column == firstrow_columnindex)
|
|
continue;
|
|
else
|
|
minor[row_minor][column_minor] = B[row][column];
|
|
|
|
column_minor++;
|
|
}
|
|
|
|
row_minor++;
|
|
}
|
|
|
|
m = row_minor;
|
|
n = column_minor;
|
|
|
|
if (firstrow_columnindex % 2 == 0)
|
|
sum += B[0][firstrow_columnindex] * det(minor);
|
|
else
|
|
sum -= B[0][firstrow_columnindex] * det(minor);
|
|
|
|
}
|
|
|
|
return sum;
|
|
|
|
}
|
|
}
|