Read SICP...together <3

I propose that those of us who haven't yet read SICP resolve to beginning reading SICP right now. Let's use this thread for discussion, Q&A, and sharing our solutions to the exercises. Come, let us share in the joy, the pain, and the triumph. There will be Knights of the Lambda Calculus badges for all.

http://mitpress.mit.edu/sicp/full-text/book/book.html

>>17
     (PRC () (values -8
                     (error "Timezone for PRC not implemented -
Don't forget that 10000 students were murdered by the government
of the \"People's Republic of China\" in June 1989!"
     )       )       )

Clisp:
[1]> (time (loop for i from 0 to 1000000 summing i))
Real time: 1.898606 sec.
Run time: 1.896119 sec.
Space: 9648 Bytes
500000500000

SBCL:
* (time (loop for i from 0 to 1000000 summing i))

Evaluation took:
  0.009 seconds of real time
  0.008001 seconds of total run time (0.008001 user, 0.000000 system)
  88.89% CPU
  20,736,155 processor cycles
  0 bytes consed
 
500000500000

(defun f (x)
  (if (zerop x) 0 (f (1- x))))

Clisp:
[2]> (f 1000000)

*** - Program stack overflow. RESET

SBCL:
* (f 1000000)

0