Solve 2016 days 6 to 8.

2016/d6.py

@@ -0,0 +1,25 @@
+from lib import *
+
+data = open(0).read().strip()
+second = True
+
+p = ""
+for row in zip(*data.splitlines()):
+    counts = {}
+    for l in LETTERS_LOWER:
+        counts[l] = row.count(l)
+    maxc = 0
+    minc = 999
+    c = ""
+    for l, count in counts.items():
+        if second:
+            if count > 0 and count < minc:
+                minc = count
+                c = l
+        else:
+            if count > maxc:
+                maxc = count
+                c = l
+    p += c
+
+print(p)

2016/d7.py

@@ -0,0 +1,72 @@
+from lib import *
+
+data = open(0).read().strip()
+first = False
+
+def has_abba(xs):
+    for i in range(len(xs) - 3):
+        if xs[i] == xs[i + 3] and xs[i + 1] == xs[i + 2] and xs[i] != xs[i + 1]:
+            return True
+    return False
+
+if first:
+    r = 0
+    for line in data.splitlines():
+        is_abba = False
+
+        xs = ""
+        for c in line:
+            if c == "[":
+                if has_abba(xs):
+                    is_abba = True
+                xs = ""
+            elif c == "]":
+                if has_abba(xs):
+                    is_abba = False
+                    xs = ""
+                    break
+                xs = ""
+            xs += c
+
+        if xs != "" and has_abba(xs):
+            is_abba = True
+
+        if is_abba:
+            r += 1
+    print(r)
+else:
+    def abas(xs) -> set:
+        r = set()
+        for i in range(len(xs) - 2):
+            if not in_square and xs[i] == xs[i + 2] and xs[i] != xs[i + 1]:
+                r.add(xs[i:i+3])
+        return r
+
+    def babs(xs) -> set:
+        r = set()
+        for i in range(len(xs) - 2):
+            if not in_square and xs[i] == xs[i + 2] and xs[i] != xs[i + 1]:
+                r.add(xs[i + 1] + xs[i] + xs[i + 1])
+        return r
+
+    r = 0
+    for line in data.splitlines():
+        aba, bab = set(), set()
+        in_square = False
+        xs = ""
+        for c in line:
+            if c == "[":
+                aba |= abas(xs)
+                xs = ""
+            elif c == "]":
+                bab |= babs(xs)
+                xs = ""
+            else:
+                xs += c
+        if xs != "":
+            aba |= abas(xs)
+
+        if aba & bab:
+            r += 1
+
+    print(r)

2016/d8.py

@@ -0,0 +1,53 @@
+from lib import *
+
+data = open(0).read().strip()
+
+cols = 50
+rows = 6
+pxs = []
+
+def display(pxs):
+    for r in range(rows):
+        row = ""
+        for c in range(cols):
+            if (r, c) in pxs:
+                row += "#"
+            else:
+                row += "."
+        print(row)
+    print()
+
+for line in data.splitlines():
+    if "rect" in line:
+        col, row = str_to_ints(line)
+        for r in range(row):
+            for c in range(col):
+                if r < rows and c < cols:
+                    pxs.append((r, c))
+    elif "row" in line:
+        npxs = []
+        row, offset = str_to_ints(line)
+        for (r, c) in pxs:
+            if r == row:
+                nc = (c + offset) % cols
+                npxs.append((r, nc))
+            else:
+                npxs.append((r, c))
+        pxs = npxs
+    elif "column" in line:
+        npxs = []
+        col, offset = str_to_ints(line)
+        for (r, c) in pxs:
+            if c == col:
+                nr = (r + offset) % rows
+                npxs.append((nr, c))
+            else:
+                npxs.append((r, c))
+        pxs = npxs
+    else:
+        assert False
+
+    pxs = list(set(pxs))
+
+print(len(pxs))
+display(pxs) # EOARGPHYAO

README.md

@@ -38,3 +38,7 @@ written in Python.
 - Day 3: 11:20 Ugly and slow.
 - Day 4: 21:05 -__-
 - Day 5: 29:35 -___-
+- Day 6: 4:20 okay
+- Day 7: 31:20 hmm
+- Day 8: 14:50 meh
+- Day 9: