Add kotlin code for the utils file (#1175)

* feat(kotlin): add kotlin code for utils file. * Update ListNode.kt * Update PrintUtil.kt --------- Co-authored-by: Yudong Jin <krahets@163.com>
2026-08-21 07:47:14 +00:00 · 2024-03-25 19:15:40 +08:00
parent 5e77a64341
commit 5ec5ef9af0
4 changed files with 238 additions and 0 deletions
@@ -0,0 +1,106 @@
+/**
+ * File: PrintUtil.kt
+ * Created Time: 2024-01-25
+ * Author: curtishd (1023632660@qq.com)
+ */
+
+package utils
+
+import java.util.*
+
+class Trunk(var prev: Trunk?, var str: String)
+
+/* 打印矩阵（Array） */
+fun <T> printMatrix(matrix: Array<Array<T>>) {
+    println("[")
+    for (row in matrix) {
+        println("  $row,")
+    }
+    println("]")
+}
+
+/* 打印矩阵（List） */
+fun <T> printMatrix(matrix: List<List<T>>) {
+    println("[")
+    for (row in matrix) {
+        println("  $row,")
+    }
+    println("]")
+}
+
+/* 打印链表 */
+fun printLinkedList(h: ListNode?) {
+    var head = h
+    val list = ArrayList<String>()
+    while (head != null) {
+        list.add(head.value.toString())
+        head = head.next
+    }
+    println(list.joinToString(separator = " -> "))
+}
+
+/* 打印二叉树 */
+fun printTree(root: TreeNode?) {
+    printTree(root, null, false)
+}
+
+/**
+ * 打印二叉树
+ * This tree printer is borrowed from TECHIE DELIGHT
+ * https://www.techiedelight.com/c-program-print-binary-tree/
+ */
+fun printTree(root: TreeNode?, prev: Trunk?, isRight: Boolean) {
+    if (root == null) {
+        return
+    }
+
+    var prevStr = "    "
+    val trunk = Trunk(prev, prevStr)
+
+    printTree(root.right, trunk, true)
+
+    if (prev == null) {
+        trunk.str = "———"
+    } else if (isRight) {
+        trunk.str = "/———"
+        prevStr = "   |"
+    } else {
+        trunk.str = "\\———"
+        prev.str = prevStr
+    }
+
+    showTrunks(trunk)
+    println(" ${root.value}")
+
+    if (prev != null) {
+        prev.str = prevStr
+    }
+    trunk.str = "   |"
+
+    printTree(root.left, trunk, false)
+}
+
+fun showTrunks(p: Trunk?) {
+    if (p == null) {
+        return
+    }
+    showTrunks(p.prev)
+    print(p.str)
+}
+
+/* 打印哈希表 */
+fun <K, V> printHashMap(map: Map<K, V>) {
+    for ((key, value) in map) {
+        println(key.toString() + " -> " + value)
+    }
+}
+
+/* 打印堆 */
+fun printHeap(queue: Queue<Int>?) {
+    val list = queue?.let { ArrayList(it) }
+    print("堆的数组表示：")
+    println(list)
+    println("堆的树状表示：")
+    val root = list?.let { TreeNode.listToTree(it) }
+    printTree(root)
+}