Матричный метод решения системы уравнений

defdbl a,b,c,d,x
N=3
open "A1.dat" for input as#1: open "B1.dat" for input as#2
?:? " Zadana matrica A: " :for i=1 to N: for j=1 to N: input #1, a(i,j)
? using "###.##"; a(i,j);:next j:?:next i: for i=1 to N: input #2, b(i):next i
gosub det:gosub dop
if d=0 then ? "Matrica virojdennaya"
? "   Obratnaya matrica C"
for i = 1 to N: for j=1 to N: c(i,j) = (-1)^(i+j)*d(i,j)/d
? using "####.#####"; c(i,j);:next j:?:next i
?:? "Reshenie zadachi" :? "Zadannyj vektor B"
for i=1 to N:? using "####.##"; b(i);:next i:
?:? "  x(1)   x(2)   x(3)"
for i=1 to N: x(i)=0: for k=1 to N:x(i)=x(i)+b(k)*c(k,i):next k
? using "##.####### "; x(i);: next i
?:? "Proverka (Sopostavit s b(i)" : for i = 1 to N: dev(i) = 0: for k = 1 to N
dev(i) = dev(i) + a(i,k) * x(k): next k: ? using " ###.###### "; dev(i);:next i
close 1,2:end
det:
d = a(1,1)*a(2,2)*a(3,3)+a(1,2)*a(2,3)*a(3,1)+a(2,1)*a(3,2)*a(1,3)
d = d - a(3,1) * a(2,2) * a(1,3) - a(1,3) * a(2,1) * a(3,3) - a(1,1) * a(3,2) * a(2,3): return
dop:
d(1,1) = a(2,2) * a(3,3) - a(2,3) * a(3,2): d(1,2) = a(2,1) * a(3,3) - a(2,3) * a(3,1)