Shift Solution

ldsum := 0.0;

rdsum := 0.0;

temp := A;

temp2 := A;

for row := 2 to n do

[east of R] wrap temp;

[row..n, 1..n] temp := temp@east; -- rotate row i west by i-1 elements

[west of R] wrap temp2;

[row..n, 1..n] temp2 := temp2@west; -- rotate row i east by i-1 elements

end;

/* Process the forward diagonals */

[south of R] temp := *<<[R] temp; -- calculate column products

[south of R] ldsum := +<< temp; -- sum the products

/* Process the reverse diagonals */

[south of R] temp2 := *<<[R] temp2; -- calculate column products

[south of R] rdsum := +<< temp2; -- sum the products

return ldsum - rdsum; -- Return the determinant

end;