diff --git a/d12/draw.py b/d12/draw.py
new file mode 100644
index 0000000..9c4b187
--- /dev/null
+++ b/d12/draw.py
@@ -0,0 +1,58 @@
+import sys
+import networkx as netx
+
+M = [ list(l) for l in sys.stdin.read().splitlines() ]
+H = len(M)
+W = len(M[0])
+START = tuple()
+END = tuple()
+G = netx.DiGraph()
+
+for x in range(H):
+    for y in range(W):
+        k = (x,y)
+        v = M[x][y]
+        if v == 'S':
+            START = k
+            v = 'a'
+        if v == 'E':
+            END = k
+            v = 'z'
+        v = ord(v)
+        for dx,dy in [(-1,0),(1,0),(0,-1),(0,1)]:
+            nx, ny = (x+dx, y+dy)
+            if nx>=0 and nx<H and ny>=0 and ny<W:
+                nk = (nx,ny)
+                nv = M[nx][ny]
+                if nv == 'S':
+                    nv = 'a'
+                if nv == 'E':
+                    nv = 'z'
+                nv = ord(nv)
+                dv = nv - v
+                if dv <=1:  # can go down !
+                    G.add_edge(k,nk)
+
+# palette by https://gka.github.io/palettes/#/26|s|ffffe5,fe9929,662506|ffffe0,ff005e,93003a|1|1
+C = [ '#ffffe5','#fff4d3','#ffeac1','#ffdfb0','#ffd49f','#fcca91','#f8c084','#f3b677','#edac6c','#e7a361','#e19a58','#da914e','#d38846','#cb803e','#c47737','#bc6f30','#b3672a','#ab5f24','#a3571f','#9a501a','#924816','#894112','#803a0e','#77330b','#6f2c09','#662506']
+c2i = lambda x: int("0x"+x,16)
+C = [ " ".join(map(str,map(c2i,[c[1:3],c[3:5],c[5:]]))) for c in C ]
+
+for x in range(H):
+    for y in range(W):
+        v = M[x][y]
+        if v == 'S':
+            v = 'a'
+        if v == 'E':
+            v = 'z'
+        M[x][y] = C[ord(v)-ord("a")]
+
+S = netx.shortest_path(G, START, END)
+
+print("P3")
+print("81 41")
+print("255")
+
+for (x,y) in S:
+    M[x][y] = "64 196 64"
+print("\n".join("\n".join(l) for l in M))
diff --git a/d12/input b/d12/input
new file mode 100644
index 0000000..2e02b7c
--- /dev/null
+++ b/d12/input
@@ -0,0 +1,41 @@
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