2024 day 4 solved

2024/2.py

@@ -2,10 +2,8 @@ lines = [[int(n) for n in l.split()] for l in open("input.txt", 'r').read().spli
 
 unsafe, unsafe2 = 0, 0
 
-for report in lines:
-    if report[0] == report[1]:
-        unsafe += 1
-        continue
+def checksafe(report, recursive):
+    global unsafe, unsafe2 
 
     trend = -1 if report[0] > report[1] else 1
 
@@ -14,8 +12,26 @@ for report in lines:
             or (trend == 1 and report[i] > report[i+1]) \
             or (report[i] == report[i+1]) \
             or (abs(report[i] - report[i+1]) > 3):
-            
-            unsafe += 1
-            break
+            if recursive:
+                return False
+            else:
+                unsafe += 1
+                # ????????? there's no way this is how this is should be done
+                if not (checksafe(l[:i-1] + l[i:], True) or checksafe(l[:i] + l[i+1:], True) or checksafe(l[:i+1] + l[i+2:], True)):
+                    unsafe2 += 1
+                    return False
+                return True
+
+    return True
+
+for l in lines:
+    if l[0] == l[1]:
+        unsafe += 1
+        if not (checksafe(l[1:], True) or checksafe(l[:1] + l[2:], True)):
+            unsafe2 += 1
+            continue
+    else:
+        checksafe(l, False)
 
-print(len(lines)-unsafe)
+print(len(lines)-unsafe)
+print(len(lines)-unsafe2)

2024/3.py

@@ -0,0 +1,25 @@
+import re
+
+lines = [l for l in open("input.txt", 'r').read().splitlines()]
+
+summa, summa2, do = 0, 0, True
+
+for l in lines:
+    x2 = [i.span() for i in re.finditer(r"mul\([0-9]{1,3},[0-9]{1,3}\)|do\(\)|don't\(\)", l)]
+
+    for start,end in x2:
+        if l[start:end] == 'do()':
+            do = True
+        elif l[start:end] == 'don\'t()':
+            do = False
+        elif do:
+            tup = l[start:end].split(',')
+            prod = int(tup[0][4:]) * int(tup[1][:-1])
+            summa2 += prod
+            summa += prod
+        else :
+            tup = l[start:end].split(',')
+            summa += int(tup[0][4:]) * int(tup[1][:-1])
+
+print(summa)
+print(summa2)

2024/4.py

@@ -0,0 +1,33 @@
+import re
+
+lines = [l for l in open("input.txt", 'r').read().splitlines()]
+
+linesVert, linesDiag1, linesDiag2 = [], [], []
+count, count2, width = 0, 0, len(lines[0])
+
+for i in range(width):
+    string, string2, string3 = "", "", ""
+    for j in range(len(lines)):
+        string += lines[j][i]
+        string2 += lines[j][(i+j)%width]
+        string3 += lines[width-j-1][(i+j)%width]
+    
+    linesDiag1.append(string2[:width - i])
+    linesDiag1.append(string2[width - i:])
+    linesDiag2.append(string3[:width - i])
+    linesDiag2.append(string3[width - i:])
+    linesVert.append(string)
+
+for l in lines + linesVert + linesDiag1 + linesDiag2:
+    count += len(re.findall(r"(?=(XMAS|SAMX))", l))
+
+for i in range(width-2):
+    for j in range(len(lines)-2):
+        diag1 = lines[j][i] + lines[j+1][i+1] + lines[j+2][i+2]
+        diag2 = lines[j+2][i] + lines[j+1][i+1] + lines[j][i+2]
+        if re.search(r"MAS|SAM", diag1) != None and re.search(r"MAS|SAM", diag2) != None:
+            count2 += 1
+
+
+print(count)
+print(count2)