diff --git a/d12/part1.block.py b/d12/part1.block.py
new file mode 100644
index 0000000..0d79e99
--- /dev/null
+++ b/d12/part1.block.py
@@ -0,0 +1,40 @@
+import sys
+
+def strset(s,i,c):
+    return s[:i]+c+s[i+1:]
+
+def next(pat, nums, patc=''):  # pat must terminiate with '.'
+    #print(f"next {pat=} {nums=} ({patc=}), {len(pat)+len(patc)}")
+    if len(nums) == 0:
+        if pat.find('#')<0:
+            #print("valid", patc)
+            return 1
+        return 0
+    # find all ways to build first block
+    l = nums[0]
+    block = '#'*l
+    rest = sum(nums[1:])
+    n = 0
+    m = len(pat)-l-rest
+    for i in range(m):
+        # if can build block:
+        z = pat[i:i+l].replace('?','#')
+        #print(f"{i=}/{m=} {z=}, {pat[i+l]}")
+        if z == block:
+            ##print("march, and ", pat[i+l])
+            if pat[:i].find('#')<0 and not pat[i+l] == '#':  # '.' or '?'
+                #pat = strset(pat, i+l, '.')
+                # recurse
+                r = next(pat[i+l+1:], nums[1:], patc+pat[:i].replace('?','.')+z+'.')
+                if r > 0:
+                    n += r
+    return n
+
+S= 0
+for i,l in enumerate(sys.stdin.read().splitlines()):
+    pattern, snums  = l.split(' ')
+    nums = list(map(int,snums.split(',')))
+    n = next(pattern+'.', nums)
+    print(i,l,n)
+    S += n
+print(S)
diff --git a/d12/part1.len.py b/d12/part1.len.py
new file mode 100644
index 0000000..00895f5
--- /dev/null
+++ b/d12/part1.len.py
@@ -0,0 +1,37 @@
+import sys
+
+def valid(pat:str, nums:list[int]):
+    pat += '.'
+    c = 0
+    for i,p in enumerate(pat):
+        if p == '#':
+            c += 1
+        else:
+            if c>0:
+                if c == nums[0]:
+                    c = 0
+                    nums = nums[1:]
+                    if len(nums) == 0:
+                        return 1 if pat[i:].find('#')<0 else 0
+                else:
+                    return 0
+    return 0
+
+def next(pattern, nums):
+    i = pattern.find('?')
+    if i < 0:
+        v = valid(pattern, nums)
+        if v == 1:
+            print("valid", pattern)
+        return v
+    else:
+        return next(pattern[:i]+'.'+pattern[i+1:], nums)+next(pattern[:i]+'#'+pattern[i+1:], nums)
+
+S= 0
+for i,l in enumerate(sys.stdin.read().splitlines()):
+    pattern, snums  = l.split(' ')
+    nums = list(map(int,snums.split(',')))
+    n = next(pattern, nums)
+    print(i,l,n)
+    S += n
+print(S)
diff --git a/d12/part1.list.py b/d12/part1.list.py
new file mode 100644
index 0000000..7c40b89
--- /dev/null
+++ b/d12/part1.list.py
@@ -0,0 +1,31 @@
+import sys
+
+def valid(pattern, nums):
+    l = []
+    c = ''
+    for p in pattern:
+        if p == '#':
+            c+=p
+        else:
+            if len(c):
+                l.append(c)
+                c = ''
+    if len(c):
+        l.append(c)
+        c = ''
+    l = [len(m) for m in l]
+    return 1 if l == nums else 0
+
+def next(pattern, nums):
+    i = pattern.find('?')
+    if i < 0:
+        return valid(pattern, nums)
+    else:
+        return next(pattern[:i]+'.'+pattern[i+1:], nums)+next(pattern[:i]+'#'+pattern[i+1:], nums)
+
+S= 0
+for l in sys.stdin.read().splitlines():
+    pattern, snums  = l.split(' ')
+    nums = list(map(int,snums.split(',')))
+    S += next(pattern, nums)
+print(S)