day 17-19

2021/19-1.py

@@ -0,0 +1,81 @@
+import sys; sys.dont_write_bytecode = True;
+from utils import *
+import typing
+
+
+def do_case(inp: str, sample=False):
+    # READ THE PROBLEM FROM TOP TO BOTTOM OK
+    def sprint(*a, **k): sample and print(*a, **k)
+    lines: typing.List[str] = inp.splitlines()
+    paras: typing.List[typing.List[str]] = lmap(str.splitlines, inp.split("\n\n"))
+    out = 0
+
+    scanners = []
+    for para in paras:
+        points = lmap(ints, para[1:])
+        scanners.append(points)
+        # print(len(points))
+    
+    # assume scanner 0 is good
+
+    FACINGS = [x for i in [-1, 1] for x in [[i, 0, 0], [0, i, 0], [0, 0, i]]]
+
+    def cross(a, b):
+        c = [a[1]*b[2] - a[2]*b[1],
+            a[2]*b[0] - a[0]*b[2],
+            a[0]*b[1] - a[1]*b[0]]
+
+        return c
+    
+    def common(a, b):
+        aset = set(map(tuple, a))
+        # return b's points, but now relative to a
+        for facing in FACINGS:
+            for up in [f for f in FACINGS if all(abs(x) != abs(y) for x, y in zip(f, facing) if x or y)]:
+                
+                # facing's
+                right = cross(facing, up)
+
+                matrix = [facing, up, right]
+                new_b = [matvec(matrix, vec) for vec in b]
+
+                for a_point in a:
+                    for b_point in new_b:
+                        # assume they're the same
+                        # add a-b to all b
+                        delta = padd(a_point, pneg(b_point))
+                        new_new_b = [padd(delta, b) for b in new_b]
+                        if len(aset.intersection(map(tuple, new_new_b))) >= 12:
+                            return new_new_b
+        return None
+    
+    # if sample:
+    #     print(common(scanners[0], scanners[1]))
+    #     quit()
+    good_scanners = [None] * len(scanners)
+    good_scanners[0] = scanners[0]
+    done_scanners = [False] * len(scanners)
+    while True:
+        for i in range(len(scanners)):
+            if good_scanners[i] and not done_scanners[i]:
+                for j in range(len(scanners)):
+                    if i != j and good_scanners[j] is None:
+                        test = common(good_scanners[i], scanners[j])
+                        # sprint(test)
+                        if test is not None:
+                            good_scanners[j] = test
+                done_scanners[i] = True
+        print(done_scanners, lmap(bool, good_scanners))
+        if all(done_scanners):
+            break
+    
+    out = set(tuple(point) for points in good_scanners for point in points)
+    out = len(out)
+
+    
+    if out:
+        print("out:    ", out)
+    return  # RETURNED VALUE DOESN'T DO ANYTHING, PRINT THINGS INSTEAD
+
+with open('./2021/19.input') as input_file:
+	do_case(input_file.read())