Create binary-tree 2-m.go

bench/algorithm/binarytrees/2-m.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+    "fmt"
+    "os"
+    "strconv"
+    "sync"
+)
+
+type Node struct {
+    left  *Node
+    right *Node
+}
+
+func bottomUpTree(depth int) *Node {
+    if depth <= 0 {
+        return &Node{}
+    }
+    n := &Node{}
+    n.left = bottomUpTree(depth - 1)
+    n.right = n.left 
+    return n
+}
+
+func (n *Node) itemCheck() int {
+    if n.left == nil {
+        return 1
+    }
+    return 1 + n.left.itemCheck()*2
+}
+
+const minDepth = 4
+
+func main() {
+    var maxDepth int
+    if len(os.Args) > 1 {
+        var err error
+        if maxDepth, err = strconv.Atoi(os.Args[1]); err != nil {
+            maxDepth = 5 
+        }
+    } else {
+        maxDepth = 5
+    }
+
+    if minDepth+2 > maxDepth {
+        maxDepth = minDepth + 2
+    }
+    stretchDepth := maxDepth + 1
+
+    check := bottomUpTree(stretchDepth).itemCheck()
+    fmt.Printf("stretch tree of depth %d\t check: %d\n", stretchDepth, check)
+
+    longLivedTree := bottomUpTree(maxDepth)
+
+    var wg sync.WaitGroup
+    for depth := minDepth; depth <= maxDepth; depth += 2 {
+        depth := depth // captura a variável para o escopo do loop
+        wg.Add(1)
+        go func() {
+            defer wg.Done()
+            iterations := 1 << uint(maxDepth-depth+minDepth)
+            check := 0
+
+            for i := 0; i < iterations; i++ {
+                check += bottomUpTree(depth).itemCheck()
+            }
+            fmt.Printf("%d\t trees of depth %d\t check: %d\n", iterations, depth, check)
+        }()
+    }
+    wg.Wait()
+    fmt.Printf("long lived tree of depth %d\t check: %d\n", maxDepth, longLivedTree.itemCheck())
+}