SparrowOSTS_121127.ISO

SparrowOS/Demo/Graphics/CommonAncestor.CPP

@@ -0,0 +1,119 @@
+#define N	32
+ 
+class Node
+{
+  Node *left,*right;
+  I64 n;
+};
+ 
+I64 n1,n2,common_ancestor;
+Node *root;
+ 
+#define X_SPACING	16
+#define Y_SPACING	45
+#define ARROW_SPACING	3
+ 
+U0 ShowTree(CDC *dc,Node *tempn,I64 *_node_x,I64 *_tree_x,I64 y)
+{
+  I64 node_x;
+  if (tempn) {
+    if (tempn->left) {
+      ShowTree(dc,tempn->left,&node_x,_tree_x,y+Y_SPACING);
+      dc->color=BLUE;
+      GrArrow3(dc,*_tree_x,y,0,node_x+ARROW_SPACING,y+Y_SPACING-ARROW_SPACING,0);
+    }
+    if (tempn->n==n1 || tempn->n==n2) {
+      if (tempn->n==common_ancestor)
+	dc->color=YELLOW;
+      else
+	dc->color=RED;
+    } else if (tempn->n==common_ancestor)
+      dc->color=GREEN;
+    else
+      dc->color=BLUE;
+ 
+    *_node_x=*_tree_x;
+    GrPrintF(dc,*_node_x,y,"%d",tempn->n);
+    *_tree_x+=X_SPACING;
+ 
+    if (tempn->right) {
+      ShowTree(dc,tempn->right,&node_x,_tree_x,y+Y_SPACING);
+      dc->color=BLUE;
+      GrArrow3(dc,*_node_x,y,0,node_x-ARROW_SPACING,y+Y_SPACING-ARROW_SPACING,0);
+    }
+  }
+}
+ 
+U0 DrawIt(CTask *,CDC *dc)
+{
+  I64 node_x=0,tree_x=0;
+  ShowTree(dc,root,&node_x,&tree_x,20);
+}
+
+U0 TreeAdd(Node **_root,Node *tempn)
+{
+  Node *root=*_root;
+  if (!root)
+    *_root=tempn;
+  else if (tempn->n==root->n)
+    Free(tempn);
+  else if (tempn->n<root->n)
+    TreeAdd(&root->left,tempn);
+  else
+    TreeAdd(&root->right,tempn);
+}
+
+U0 TreeNew()
+{
+  I64 i;
+  Node *tempn;
+  for (i=0;i<N;i++) {
+    tempn=CAlloc(sizeof(Node));
+    tempn->n=RandU16%N;
+ 
+    if (i==N-1)
+      n1=tempn->n;
+    else if (i==N-2)
+      n2=tempn->n;
+ 
+    TreeAdd(&root,tempn);
+    Sleep(50);
+  }
+}
+ 
+U0 TreeCommonAncestorFind(Node *root)
+{
+  if (root && root->n!=n1 && root->n!=n2) {
+    common_ancestor=root->n;
+    if (n1<root->n && n2<root->n)
+      TreeCommonAncestorFind(root->left);
+    else if (n1>root->n && n2>root->n)
+      TreeCommonAncestorFind(root->right);
+  }
+}
+ 
+U0 TreeCommonAncestor()
+{ //Make tree and find common ancestor to n1 & n2.
+  root=NULL;
+  n1=n2=common_ancestor=0;
+ 
+  SettingsPush; //See $LK,"SettingsPush","MN:SettingsPush"$
+  Fs->draw_it=&DrawIt;
+  DocClear;
+  "Scroll with {CTRL-Left Grab}.\n";
+  try {
+    TreeNew;
+    TreeCommonAncestorFind(root);
+    PressAKey;
+  } catch
+    CatchAll;
+  SettingsPop;
+}
+
+TreeCommonAncestor;
+/*
+Be careful with recursive routines in SparrowOS
+because the stack does not grow and will overflow.
+
+See $LK,"::/SparrowOS/Demo/StkGrow.CPP.Z","FI:::/SparrowOS/Demo/StkGrow.CPP.Z"$.
+*/