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function [x, iteracje] = ils(A, b, omega, tol)

n= length(A(1,:));
maxit = 1000;
x = zeros(n,1);

D = diag(diag(A));
L = tril(A)-D;
U = triu(A)-D;

B = ((D+omega*L)^(-1))*((1-omega)*D-omega*U);
c = omega*(D+omega*L)^(-1)*b';



iteracje = 0;
temp  = zeros(n,1);

while( iteracje < 1000 )

    temp = x;
    x = B*x + c;
    iteracje = iteracje + 1;

    if norm(x) > tol^(-1/2)
        iteracje = -1;
        break;
    end

    if norm(x-temp) < tol
        break;
    end
end

if iteracje == 1000
    iteracje = -1;
end



end