1 files changed, 55 insertions, 1 deletions
diff --git a/ps07_amb/bnewbold_ps07.txt b/ps07_amb/bnewbold_ps07.txt
index 27bc791..aa91f6a 100644
--- a/ps07_amb/bnewbold_ps07.txt
+++ b/ps07_amb/bnewbold_ps07.txt
@@ -13,7 +13,61 @@ the who-owns-what-yacht pairings by hand because it only takes one elimination.
 
 [see code in bnewbold_ps07_work.scm]
 
-Problem 7.2: 
+Problem 7.2: Continuation Returning
+---------------------------------------
+At the return of every branch I printed the result; if a #t result thunked up
+through the return structure normally, there would be a series of statements
+printed, instead there's just the #t.
+
+[see code in bnewbold_ps07_work.scm]
+
+Problem 7.3: Depth vs. Breadth
+--------------------------------
+The breadth-first essentially trys all combinations by incrementing the final
+element of the triple while the depth first increments the first digit; the
+first-digit incrementing comes to (12 16 20) with fewer steps. I checked this
+by pp-ing every tested triple.
+
+The extra fail calls are coming from the require in integer-between; eg when
+i=10, j increments up to j=20 at which point the selection of k fails.
+
+The depth-first method would try to first enumerate all possible first-digits
+then proceed to the second digits; with a-pythagorean-triple-from, the number
+of possible first-digits is infinite, so evaluation would never proceed beyond
+that point.
+
+[see code in bnewbold_ps07_work.scm]
+
+Problem 7.4: No Such Problem?
+-----------------------------------------------
+
+Problem 7.5: Alternative Alternation Orders
+-----------------------------------------------
+I wrote an itinerary generator based on budget; you wouldn't want to go through
+the itineraries with a regular left-to-right type schedule or really any order,
+you would want a randomly different itinerary (fitting the constraints and
+not something you've done before) every time.
+
+In the end though, the list comes out fairly ordered, I guess the only way to
+really get a totally random list would be to build an entire search schedule
+without evaluating the last step of each, then randomize the entire schedule
+and go through evaluating.
+
+[see code in bnewbold_ps07_work.scm]
+
+Problem 7.6: 
 --------------------------------
+This doesn't seem too mysterious to me, maybe I don't fully understand the 
+question. When each variable {x,y,z} is assigned an amb value withing a let,
+that value (within the let environment) is stored in following continuations.
+When using set! the variable values are not stored in later continuations, or
+more technically, the set! alters the value of the variables in all
+continuations (globally). So when a continuation gets called, the value of
+{x,y,z} is not the value from when that continuation was stored, but global 
+value, aka the last value set!.
 
+When going depth-first, the continuations reach back far enough that the 
+variables get reset properly. Another way of stating this is that the order of
+evaluation procedes in just the right order so that the globaly set! value
+is the appropriate one for each individual alternative continuation.