load("__common__.sage")
def generator():
A = matrix([[choice([-1,1])*randrange(1,7) for _ in range(0,4)] for _ in range(0,4)])
line = randint(1,3)
indices = choice(([(line,0),(line,1),(line,2),(line,3)],[(0,line),(1,line),(2,line),(3,line)]))
shuffle(indices)
A[indices[0]]=0
A[indices[1]]=0
A[indices[2]]=choice([-1,1])
A[indices[3]]=choice([-1,1])*randrange(2,4)
A[randint(0,3),randint(0,3)]=0
return {
"matrix": A,
"determinant": A.determinant()
}