C Programming Code Examples C > Arrays and Matrices Code Examples Program to calculate determinant of 3x3 matrix Program to calculate determinant of 3x3 matrix Write a C program to read elements in a matrix and find determinant of the given matrix. C program to find determinant of a 2x2 matrix and 3x3 matrix. Logic to find determinant of a matrix in C programming. #include <stdio.h> #define SIZE 3 // Matrix size int main() { int A[SIZE][SIZE]; int row, col; int a, b, c, d, e, f, g, h, i; long det; /* Input elements in matrix A from user */ printf("Enter elements in matrix of size 3x3: \n"); for(row=0; row<SIZE; row++) { for(col=0; col<SIZE; col++) { scanf("%d", &A[row][col]); } } /* * Used as a temporary variables to make calculation easy * | | * | a b c | * | d e f | * | g h i | * | | */ a = A[0][0]; b = A[0][1]; c = A[0][2]; d = A[1][0]; e = A[1][1]; f = A[1][2]; g = A[2][0]; h = A[2][1]; i = A[2][2]; /* det(A) = a(ei - fh) - b(di - fg) + c(dh - eg) */ det = (a*(e*i - f*h)) - (b*(d*i - f*g)) + (c*(d*h - e*g)); printf("Determinant of matrix A = %ld", det); return 0; }
