Finished 07a in racket.

Author: zenspider

zenspider/2019/07.rkt

@@ -0,0 +1,59 @@
+#lang racket
+
+(require "../myutils.rkt")
+(require "int_code.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (run-amp mem phases [input '(0)])
+  (for/fold ([input input]
+             #:result (first input))
+            ([phase (in-list phases)])
+    (execute mem (cons phase input))))
+
+(define (problem-07a input)
+  (define mem (mem-parse input))
+
+  (for/fold ([max (void)])
+            ([phases (in-permutations (range 0 5))])
+    (let ([result (cons (run-amp mem phases) (list phases))])
+      (cond [(void? max) result]
+            [(< (car max) (car result)) result]
+            [else max]))))
+
+(module+ test
+  (define-simple-check (check-int-code/5 input program output)
+    (check-equal? (execute program input)
+                  output))
+
+  (define input/1 "3,15,3,16,1002,16,10,16,1,16,15,15,4,15,99,0,0")
+  (define input/2 "3,23,3,24,1002,24,10,24,1002,23,-1,23,101,5,23,23,1,24,23,23,4,23,99,0,0")
+  (define input/3 "3,31,3,32,1002,32,10,32,1001,31,-2,31,1007,31,0,33,1002,33,7,33,1,33,31,31,1,32,31,31,4,31,99,0,0,0")
+
+  (check-equal? (problem-07a input/1)
+                '(43210 (4 3 2 1 0)))
+
+  (check-equal? (problem-07a input/2)
+                '(54321 (0 1 2 3 4)))
+
+  (check-equal? (problem-07a input/3)
+                '(65210 (1 0 4 3 2))))
+
+(define (problem-07b input)
+  #;
+  (argmax car
+         (for/list ([phases (sequence->list (in-permutations '(range 5 10)))])
+           (cons (run-amp mem phases) (list phases))))
+  #f)
+
+(module+ test
+  (check-equal? (problem-07b "123") 6))
+
+(module+ test
+  (displayln 'done))
+
+(module+ main
+  (define input (parse-file (data-file 07)))
+  (problem-07a input)
+  (problem-07b input))

zenspider/2019/desc/07.txt

@@ -0,0 +1,83 @@
+## --- Day 7: Amplification Circuit ---
+
+Based on the navigational maps, you're going to need to send more power to
+your ship's thrusters to reach Santa in time. To do this, you'll need to
+configure a series of amplifiers already installed on the ship.
+
+There are five _amplifiers connected in series_ ((As you can see, I know
+exactly how rockets work.)); each one receives an input signal and produces
+an output signal.  They are connected such that the first amplifier's
+output leads to the second amplifier's input, the second amplifier's output
+leads to the third amplifier's input, and so on.  The first amplifier's
+input value is `0`, and the last amplifier's output leads to your ship's
+thrusters.
+
+`    O-------O  O-------O  O-------O  O-------O  O-------O
+0 ->| Amp A |->| Amp B |->| Amp C |->| Amp D |->| Amp E |-> (to thrusters)
+    O-------O  O-------O  O-------O  O-------O  O-------O
+`
+
+The Elves have sent you some _Amplifier Controller Software_ (your puzzle
+input), a program that should run on your existing Intcode computer. Each
+amplifier will need to run a copy of the program.
+
+When a copy of the program starts running on an amplifier, it will first
+use an input instruction to ask the amplifier for its current _phase
+setting_ (an integer from `0` to `4`). Each phase setting is used _exactly
+once_, but the Elves can't remember which amplifier needs which phase
+setting.
+
+The program will then call another input instruction to get the amplifier's
+input signal, compute the correct output signal, and supply it back to the
+amplifier with an output instruction. (If the amplifier has not yet
+received an input signal, it waits until one arrives.)
+
+Your job is to _find the largest output signal that can be sent to the
+thrusters_ by trying every possible combination of phase settings on the
+amplifiers. Make sure that memory is not shared or reused between copies of
+the program.
+
+For example, suppose you want to try the phase setting sequence
+`3,1,2,4,0`, which would mean setting amplifier `A` to phase setting `3`,
+amplifier `B` to setting `1`, `C` to `2`, `D` to `4`, and `E` to `0`. Then,
+you could determine the output signal that gets sent from amplifier `E` to
+the thrusters with the following steps:
+
+* Start the copy of the amplifier controller software that will run on
+  amplifier `A`. At its first input instruction, provide it the amplifier's
+  phase setting, `3`.  At its second input instruction, provide it the input
+  signal, `0`.  After some calculations, it will use an output instruction to
+  indicate the amplifier's output signal.
+* Start the software for amplifier `B`. Provide it the phase setting (`1`)
+  and then whatever output signal was produced from amplifier `A`. It will
+  then produce a new output signal destined for amplifier `C`.
+* Start the software for amplifier `C`, provide the phase setting (`2`) and
+  the value from amplifier `B`, then collect its output signal.
+* Run amplifier `D`'s software, provide the phase setting (`4`) and input
+  value, and collect its output signal.
+* Run amplifier `E`'s software, provide the phase setting (`0`) and input
+  value, and collect its output signal.
+
+The final output signal from amplifier `E` would be sent to the thrusters.
+However, this phase setting sequence may not have been the best one;
+another sequence might have sent a higher signal to the thrusters.
+
+Here are some example programs:
+
+* Max thruster signal _`43210`_ (from phase setting sequence
+  `4,3,2,1,0`):
+  
+  `3,15,3,16,1002,16,10,16,1,16,15,15,4,15,99,0,0`
+* Max thruster signal _`54321`_ (from phase setting sequence
+  `0,1,2,3,4`):
+  
+  `3,23,3,24,1002,24,10,24,1002,23,-1,23,
+  101,5,23,23,1,24,23,23,4,23,99,0,0`
+* Max thruster signal _`65210`_ (from phase setting sequence
+  `1,0,4,3,2`):
+  
+  `3,31,3,32,1002,32,10,32,1001,31,-2,31,1007,31,0,33,
+  1002,33,7,33,1,33,31,31,1,32,31,31,4,31,99,0,0,0`
+
+Try every combination of phase settings on the amplifiers.  _What is the
+highest signal that can be sent to the thrusters?_

zenspider/2019/input/07.txt

@@ -0,0 +1 @@
+3,8,1001,8,10,8,105,1,0,0,21,38,59,84,97,110,191,272,353,434,99999,3,9,1002,9,2,9,101,4,9,9,1002,9,2,9,4,9,99,3,9,102,5,9,9,1001,9,3,9,1002,9,5,9,101,5,9,9,4,9,99,3,9,102,5,9,9,101,5,9,9,1002,9,3,9,101,2,9,9,1002,9,4,9,4,9,99,3,9,101,3,9,9,1002,9,3,9,4,9,99,3,9,102,5,9,9,1001,9,3,9,4,9,99,3,9,101,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1002,9,2,9,4,9,99,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,2,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,2,9,4,9,3,9,1001,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,99,3,9,101,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,99,3,9,1001,9,1,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,99