day 15 part 2

day15/sol.py

@@ -19,7 +19,7 @@ def solve(file):
     for y,line in enumerate(map):
         if '@' in line:
             x = line.index('@')
-            cur = y,x
+            cur = x,y
 
     print(moves)
     for m in moves:
@@ -34,6 +34,42 @@ def solve(file):
         print("".join(line))
     print(t)
 
+
+def solve2(file):
+    map, moves = parse(file)
+    map2 = []
+    for line in map:
+        l2 = []
+        for c in line:
+            if c == '#': c = '##'
+            elif c == 'O': c = '[]'
+            elif c == '.': c = '..'
+            elif c == '@': c = '@.'
+            l2.extend(c)
+        map2.append(l2)
+    map = map2
+
+    for y,line in enumerate(map):
+        if '@' in line:
+            x = line.index('@')
+            cur = x,y
+    #print(show(map), cur)
+
+    #print(moves)
+    for m in moves:
+        #print(m)
+        assert map[cur[1]][cur[0]] == '@'
+        next, ok = move(map, cur, m)
+        cur = next
+    #print(cur)
+    t = 0
+    for y,line in enumerate(map):
+        for x,c in enumerate(line):
+            if c == '[':
+                t += y*100 + x
+        print("".join(line))
+    print(t)
+
 def move(map, cur, m):
     if m == 'v': d = (0,1)
     if m == '<': d = (-1,0)
@@ -46,6 +82,23 @@ def move(map, cur, m):
         _, ok = move(map, n, m)
         if not ok:
             return cur, False
+    elif c in "[]":
+        if m in '<>':
+            _, ok = move(map, n, m)
+            if not ok:
+                return cur, False
+        else:
+            blocks = set()
+            ok = canpush(map, n, d, blocks)
+            if not ok:
+                return cur, False
+            #print(blocks)
+            #print("before push\n", show(map))
+            for x,y in sorted(blocks, key=lambda a:( a[1]*-d[1],a[0])):
+                map[y+d[1]][x+d[0]] = map[y][x]
+                map[y][x] = '.'
+            #print("after push\n", show(map))
+
     elif c == '#':
         return cur, False
 
@@ -53,6 +106,29 @@ def move(map, cur, m):
     map[cur[1]][cur[0]] = '.'
     return n, True
 
+def show(map):
+    return '\n'.join(''.join(x) for x in map)
+
+def canpush(map, cur, d, blocks):
+    if cur in blocks:
+        return True
+    c = map[cur[1]][cur[0]]
+    if c == '.':
+        return True
+    if c not in '[]':
+        return False
+    blocks.add(cur)
+    nx, ny = (cur[0]+d[0], cur[1]+d[1])
+    if c == '[':
+        blocks.add((cur[0]+1, cur[1]))
+        nx2 = nx+1
+    else:
+        blocks.add((cur[0]-1, cur[1]))
+        nx2 = nx-1
+    return canpush(map, (nx,ny), d, blocks) and canpush(map, (nx2,ny), d, blocks)
+
 solve(open("sample1.in"))
 solve(open("sample2.in"))
+solve2(open('sample1.in'))
 solve(open("input"))
+solve2(open('input'))