Added day 2015-19 + small fix on 18

Piratmac · Piratmac · commit 44566783c791 · 2020-01-05T11:02:22.000+01:00
diff --git a/2015/18-Like a GIF For Your Yard.py b/2015/18-Like a GIF For Your Yard.py
@@ -25,7 +25,7 @@
                      "iterations": 100,
                      "expected": ['821', '886'],
                     }
-# 865 too low
+
 # -------------------------------- Control program execution -------------------------------- #
 
 case_to_test  = 'real'
diff --git a/2015/19-Medicine for Rudolph.py b/2015/19-Medicine for Rudolph.py
@@ -0,0 +1,150 @@
+# -------------------------------- Input data -------------------------------- #
+import os
+
+test_data = {}
+
+test = 1
+test_data[test]   = {"input": """e => H
+e => O
+H => HO
+H => OH
+O => HH
+
+HOH""",
+                     "expected": ['4', 'Unknown'],
+                    }
+
+test += 1
+test_data[test]   = {"input": """e => H
+e => O
+H => HO
+H => OH
+O => HH
+
+HOHOHO""",
+                     "expected": ['7', 'Unknown'],
+                    }
+
+test = 'real'
+input_file = os.path.join(os.path.dirname(__file__), 'Inputs', os.path.basename(__file__).replace('.py', '.txt'))
+test_data[test] = {"input": open(input_file, "r+").read().strip(),
+                     "expected": ['535', '212'],
+                    }
+
+# -------------------------------- Control program execution -------------------------------- #
+
+case_to_test  = 'real'
+part_to_test  = 2
+verbose_level = 1
+
+# -------------------------------- Initialize some variables -------------------------------- #
+
+puzzle_input           = test_data[case_to_test]['input']
+puzzle_expected_result = test_data[case_to_test]['expected'][part_to_test-1]
+puzzle_actual_result   = 'Unknown'
+
+
+# -------------------------------- Actual code execution -------------------------------- #
+
+molecules = set()
+from random import shuffle
+
+def find_nth(haystack, needle, n):
+    i = -1
+    for _ in range(n):
+        i = haystack.find(needle, i + len(needle))
+        if i == -1:
+            break
+    return i
+
+if part_to_test == 1:
+  source_molecule = puzzle_input.split('\n')[-1]
+  for string in puzzle_input.split('\n'):
+    if string == '' or string == source_molecule:
+      continue
+
+    source, _, replacement = string.split()
+
+
+    for i in range (1, source_molecule.count(source)+1):
+      molecules.add(source_molecule[:find_nth(source_molecule, source, i)] + replacement + source_molecule[find_nth(source_molecule, source, i)+len(source):])
+
+
+
+  puzzle_actual_result = len(molecules)
+
+
+
+
+else:
+  # This algorithm is wrong, in the sense that the result is not guaranteed (the replacements are applied in a random way...)
+  # However, it's extremely fast, and running it many times then taking the minimum should be the right way (with my input, the result was always 212...)
+  target_molecule = puzzle_input.split('\n')[-1]
+  replacements = list()
+  for string in puzzle_input.split('\n'):
+    if string == '' or string == target_molecule:
+      continue
+
+    replacement, _, source = string.split()
+    replacements.append((source, replacement))
+
+  new_molecule = target_molecule
+  step = 0
+  shuffle(replacements)
+  while puzzle_actual_result == 'Unknown':
+    molecule_before = new_molecule
+    for source, replacement in replacements:
+      step += new_molecule.count(source)
+      new_molecule = new_molecule.replace(source, replacement)
+      if new_molecule == 'e':
+        puzzle_actual_result = step
+        break
+    # Restart if we're stuck at some point
+    if molecule_before == new_molecule:
+      shuffle(replacements)
+      new_molecule = target_molecule
+      step = 0
+
+
+
+  # This would be the correct algorithm (ensures the result is correct), but it runs wayyyy too slow
+  # target_molecule = puzzle_input.split('\n')[-1]
+  # replacements = set()
+  # for string in puzzle_input.split('\n'):
+    # if string == '' or string == target_molecule:
+      # continue
+
+    # source, _, replacement = string.split()
+    # replacements.add((source, replacement))
+
+  # molecules = set('e')
+  # new_molecules = set()
+  # step = 0
+  # while puzzle_actual_result == 'Unknown':
+    # step += 1
+    # for molecule in molecules:
+      # for source, replacement in replacements:
+        # if not source in molecule:
+          # new_molecules.add(molecule)
+          # continue
+        # for i in range (1, molecule.count(source)+1):
+          # new_molecule = molecule[:find_nth(molecule, source, i)] + replacement + molecule[find_nth(molecule, source, i)+len(source):]
+          # if new_molecule == target_molecule:
+            # puzzle_actual_result = step
+            # break
+          # new_molecules.add(new_molecule)
+    # molecules = new_molecules.copy()
+    # print (step, len(molecules))
+
+
+
+# -------------------------------- Outputs / results -------------------------------- #
+
+if verbose_level >= 3:
+  print ('Input : ' + puzzle_input)
+print ('Expected result : ' + str(puzzle_expected_result))
+print ('Actual result   : '   + str(puzzle_actual_result))
+
+
+
+

Original file line number	Diff line number	Diff line change
`@@ -25,7 +25,7 @@`
`25`	`25`	`"iterations": 100,`
`26`	`26`	`"expected": ['821', '886'],`
`27`	`27`	`}`
`28`		`-# 865 too low`
	`28`	`+`
`29`	`29`	`# -------------------------------- Control program execution -------------------------------- #`
`30`	`30`
`31`	`31`	`case_to_test = 'real'`