the code should be a fortran code

Modify the Gauss-Seidel (GS) code given below to solve for x in the following set of equations a (1, 1) *x(1) + a (1,2)=x (2) + a (1,3) *x(3) + a (1,4) *x (4) = 5(1) a (2,1) *x(1) + a (2,2) ** (2) + a (2, 3) *x(3) + a (2,4) *x(4) = b (2) a(3,1) *x(1) + a (3,2) **(2) + a (3,3) ** (3) + a (3, 4) *x (4) = b (3) a (4,1) *x (1) + a(4,2) *x (2) + a (4,3)*x(3) + a(4,4) *x (4) = b (4) where a (1, 1) = 5 a (1, 2) = a (1, 3) = 10 a (1,4) = 2 a (2, 1) = 0 a (2, 2) = 4 a (2, 3) = 5 a (2, 4) = 7 a (3, 1) = -1 a (3, 2) = -6 a (3, 3) = a (3, 4) = -4 a (4,1) = S a (4,2) = -5 a (4,3) = 8 a (4,4) = 0 b (1) = 2.33 (2) = 11.38 b(3) = -5.03 b(4) = -3.04 answer x(1) = -1.23 x (2) = 0.45 x(3) = 0.67 0.89