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2026-11-06 21:43:33 +05:30
parent 8d8d7956ba
commit 4a9021d936
34 changed files with 1778 additions and 0 deletions
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+Constructing a tree from two traversals
+=======================================
+
+inorder   : [4, 2, 5, 1, 6, 3]
+preorder  : [1, 2, 4, 5, 3, 6]
+
+from inorder + preorder, one line per recursive call:
+root 1  inorder slice [0..5]  left size 3, right size 2
+  root 2  inorder slice [0..2]  left size 1, right size 1
+    root 4  inorder slice [0..0]  left size 0, right size 0
+    root 5  inorder slice [2..2]  left size 0, right size 0
+  root 3  inorder slice [4..5]  left size 1, right size 0
+    root 6  inorder slice [4..4]  left size 0, right size 0
+result    : 1(2(4,5),3(6,-))
+postorder of the result: [4, 5, 2, 6, 3, 1]
+
+from inorder + postorder the same tree comes back: 1(2(4,5),3(6,-))
+
+two different trees with the same preorder AND postorder:
+  1(2,-)  preorder [1, 2]  postorder [2, 1]
+  1(-,2)  preorder [1, 2]  postorder [2, 1]