Hey guys, I actually can noty find the exact solution given in the programme key.

Could you please explain to me whys.

Here is the programme to trace:

K=2
L=5
N=7
CALL SUBR(K+1, L, M, N)
PRINT*, K, L, M, N
STOP
END
SUBROUTINE SUBR(I1, I2, I3, I4)
K = I1+6
I1 = 5*I3 + I1
M = 3
I2 = (3*K+M) / 3
I4 = I1 **2 * M / 2
I3 = 2*I3 + 4
RETURN
END

The key says K=2 L= 10 M= 4 N= 13 but how?

Best regards.