Added 2017/20 part 2

2017/20/20.md

@@ -55,8 +55,6 @@ term?
 
 Your puzzle answer was `258`.
 
-The first half of this puzzle is complete! It provides one gold star: \*
-
 ## \-\-- Part Two \-\-- {#part2}
 
 To simplify the problem further, the GPU would like to remove any
@@ -94,8 +92,14 @@ destroyed at the time and place marked `X`. On the next tick, particle
 
 *How many particles are left* after all collisions are resolved?
 
-Answer:
+Your puzzle answer was `707`.
 
-Although it hasn\'t changed, you can still [get your puzzle
+Both parts of this puzzle are complete! They provide two gold stars:
+\*\*
+
+At this point, you should [return to your Advent calendar](/2017) and
+try another puzzle.
+
+If you still want to see it, you can [get your puzzle
 input](20/input).
 

2017/20/solution.py

@@ -1,5 +1,6 @@
 #!/bin/python3
-import sys,re,math
+import sys,re,math, numpy as np
+from collections import Counter, defaultdict
 from pprint import pprint
 sys.path.insert(0, '../../')
 from fred import get_re,list2int
@@ -35,33 +36,62 @@ if part == 1:
 #              Part 2                   #
 #                                       #
 #########################################
+
+def calculate_position_xyz(initial_position, velocity, acceleration):
+
+    velocity += acceleration
+
+    new_position = initial_position + velocity # + (0.5 * acceleration * time**2)
+    return np.array(new_position)
+
+def find_duplicate_indices(data):
+    value_to_indices = defaultdict(list)
+    for index, value in data.items():
+        value_tuple = tuple(value)  
+        value_to_indices[value_tuple].append(index)
+    
+    duplicate_indices = [index for indices in value_to_indices.values() if len(indices) > 1 for index in indices]
+    return duplicate_indices
+
 if part == 2:
-    continue           
+    with open(input_f) as file:
+        for line in file:
+            lines.append(get_re(r"^p=<(.*)>.*v=<(.*)>.*a=<(.*)>$",line.rstrip()))  
 
-    #pprint(lines)
+    for ldx,l in enumerate(lines):
+        lines[ldx] = [np.array(list2int(l.group(1).split(','))), np.array(list2int(l.group(2).split(','))), np.array(list2int(l.group(3).split(',')))]
 
-    # magnitude = []
+    particles = []
 
-    # def calculate_magnitude(vector):
-    #     return math.sqrt(sum(component ** 2 for component in vector))
+    iterations = 10000
 
-    # def find_slowest_as_time_infinite(vectors):
-    #     min_acceleration = float('inf')
-    #     slowest_item = None
-
-    #     for i, (_, a) in enumerate(vectors):
-    #         acceleration_magnitude = calculate_magnitude(a)
-    #         if acceleration_magnitude < min_acceleration:
-    #             min_acceleration = acceleration_magnitude
-    #             slowest_item = i
-        
-    #     return slowest_item
+    last_val = 0
+    range_since_last = 0
 
 
-    # vectors = []
+    for iter in range(iterations):
+        if len(lines) != last_val:
+            last_val = len(lines)
+        else:
+            range_since_last += 1
 
-    # for i in lines:
-    #     v = list2int(i.group(2).split(','))
-    #     a = list2int(i.group(3).split(','))
-    #     vectors.append((v,a))
-    # print(find_slowest_as_time_infinite(vectors))
+        if range_since_last > 100: # we dont want to run forever
+            break
+
+        positions = {}
+        length = len(lines)
+        duplicates = []
+
+        for ldx in range(length):
+            pos = []
+            p,v,a = lines[ldx]
+
+            pos = calculate_position_xyz(p, v, a)
+            positions[ldx] = pos
+            lines[ldx][0] = pos
+
+        duplicates = find_duplicate_indices(positions)
+
+        if len(duplicates) > 0:
+            lines = [item for i, item in enumerate(lines) if i not in duplicates]
+    print(len(lines))

2017/20/test.py

@@ -0,0 +1,38 @@
+import re
+from collections import namedtuple
+
+Particle = namedtuple('Particle', ['pos', 'vel', 'acc'])
+
+def parse_particle(line):
+    pos_match = re.search('p=<(-?\d+),(-?\d+),(-?\d+)>', line)
+    position = int(pos_match.group(1)), int(pos_match.group(2)), int(pos_match.group(3))
+    vel_match = re.search('v=<(-?\d+),(-?\d+),(-?\d+)>', line)
+    velocity = int(vel_match.group(1)), int(vel_match.group(2)), int(vel_match.group(3))
+    acc_match = re.search('a=<(-?\d+),(-?\d+),(-?\d+)>', line)
+    acceleration = int(acc_match.group(1)), int(acc_match.group(2)), int(acc_match.group(3))
+    return Particle(position, velocity, acceleration)
+
+def move_particle(particle):
+    new_v = tuple(v + a for v, a in zip(particle.vel, particle.acc))
+    new_p = tuple(p + v for p, v in zip(particle.pos, new_v))
+    return Particle(new_p, new_v, particle.acc)
+
+def manhattan(particle):
+    return sum(abs(k) for k in particle.pos)
+
+if __name__ == '__main__':
+    particles = [parse_particle(line) for line in open('input')]
+
+    orig = particles.copy()
+
+    for _ in range(1000):
+        particles = [move_particle(p) for p in particles]
+    print(particles.index(min(particles, key=manhattan)))
+
+    particles = orig.copy()
+    for _ in range(1000):
+        if len(set(p.pos for p in particles)) < len(particles):
+            positions = [p.pos for p in particles]
+            particles = [part for part, pos in zip(particles, positions) if positions.count(pos) == 1]
+            print(len(particles))
+        particles = [move_particle(p) for p in particles]

README.md

@@ -2,6 +2,21 @@
 
 ## 2017
 
+
+    |├───┬┴┴┴┤└──o┌┘└┤ FC├─*o────────┴──┘├┴┴┴┴┬──┘|    21**
+    |│o┬─┤   ├────┤┌─┤ LP├─┘┌──|(────────┤    ├──*|    20*
+    |└─┘o┤   ├─┐o─┘└─┤ UT├─┐└───┬┴┴┴┴┴┬┐   *┤1├──┘|    19**
+    |┌───┤   ├─┴─────┤ XR├─┴────┤     ├┘└┤   2├──*|    18**
+    |└┐o─┴┬┬┬┴───────┴┬┬┬┴──────┤   MAGI├*─┤ v├┌─┘|    17**
+    |V├─────┘o───────────┐*─────┤    CSMK├┘ ┌┤├└─┐|    16**
+    |└┴──┤[]├────────────┘└─────┴┬┬┬┬┬┴*│└┬┬┬┬┴──┘|    15**
+    |*────────────────┬────∧∧∧───┤|├───┘└┐└──────┐|    14**
+    |├──┐o────────────┘┌────|(────*o─────┴───────┤|    13**
+    |└─o└───────┬──────┼┴┴┴┴┬────o└──────────*o──┘|    12**
+    |*─────────┐└──┤|├─┤  AC├──∧∧∧──────────┐└───┐|    11**
+    |├───────┐┌┘┌┴┴┴┴┬─┤  D0├────────────*┌o└────┤|    10**
+    |└─o┌────┘└─┤  t ├─┤  vD├┌─────o*────┘└──────┘|    9**
+    |┌──┘┌──────┤  e ├─┤  TE├┘┌─────┘┌───────────*|    8**
     |│┌──o┌─┴┤ OP├──┘│o───┬───────┤  t├──┐*──────┤|    7**
     |│└──┐└──┴┬┬┬┴───┘┌───┘o─oTo──┤   ├──┘└───*┌─┘|    6**
     |└───┴───────────┐└────────┐*─┴┬┬┬┴──┤[]├─┘└─o|    5**