init commit

archive/algorithm/struct/tree/trie.c

@@ -0,0 +1,159 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MIN(a, b) a > b ? b : a
+#define bool char
+#define false 0
+#define true 1
+
+typedef struct trie *trieNode;
+typedef struct trie Trie;
+
+// 有bug的trie压缩树
+
+struct trie
+{
+    char *path;       //节点路径
+    int data;         //节点存放数据
+    trieNode brother; //兄弟节点
+    trieNode next;    //下面的节点
+};
+trieNode tree;
+
+trieNode newNode()
+{
+    trieNode tmp = malloc(sizeof(Trie));
+    memset(tmp, 0, sizeof(Trie));
+    tmp->path = "";
+    return tmp;
+}
+
+//插入数据
+void insert(trieNode tree, char *path, int data)
+{
+    //判断节点路径
+    if (tree->path == "")
+    {
+        //空路径直接插入
+        tree->path = path;
+        tree->data = data;
+        return;
+    }
+    //判断路径耦合,path大于节点路径,往next节点查找
+    //节点路径大于path,往brother找 (大小指相等的长度)
+    bool isPath = false; //表示path长度大于tree->path
+    int minLen = strlen(path);
+    if (strlen(path) > strlen(tree->path))
+    {
+        isPath = true;
+        minLen = strlen(tree->path);
+    }
+    int pathPos = 0;
+    for (pathPos = 0; pathPos < minLen; pathPos++)
+    {
+        if (path[pathPos] != tree->path[pathPos])
+        {
+            break;
+        }
+    }
+    if (pathPos == 0) //为0是全部不等,继续向下一个兄弟节点查询,除非下一个兄弟节点为null,直接插入
+    {
+        if (tree->brother == NULL)
+        {
+            trieNode tmp = newNode();
+            tmp->data = data;
+            tmp->path = path;
+            tree->brother = tmp;
+        }
+        else
+        {
+            insert(tree->brother, path, data);
+        }
+    }
+    else if (pathPos != minLen) //没有全部的相等
+    {
+        if (tree->next == NULL)
+        {
+            tree->next = newNode();
+        }
+        insert(tree->next, &path[pathPos], data);
+        insert(tree->next, &tree->path[pathPos], tree->data);
+        char *tmp = malloc(pathPos + 1);
+        memcpy(tmp, tree->path, pathPos);
+        tree->path = tmp;
+        tree->data = 0;
+    }
+    else //全部的相等
+    {
+        if (isPath) //全等,并且path大,继续往next节点查找
+        {
+            insert(tree->next, &path[pathPos], data);
+        }
+        else //全等,node->path大,
+        {
+            //空节点
+            if (tree->next == NULL)
+            {
+                tree->next = newNode();
+            }
+            char *tmp = malloc(pathPos + 1);
+            memcpy(tmp, tree->path, pathPos);
+            insert(tree->next, &tree->path[pathPos], tree->data);
+            tree->path = tmp;
+            tree->data = data;
+        }
+    }
+}
+
+trieNode search(trieNode tree, char *path)
+{
+    if (tree == NULL)
+    {
+        return NULL;
+    }
+    int pos1 = 0, pos2 = 0;
+    for (; pos2 < strlen(path); pos2++, pos1++)
+    {
+        if (tree->path[pos1] != path[pos2])
+        {
+            if (pos1 == 0) //为0则表示一个都不相等,往兄弟节点查询
+            {
+                pos1 = -1;
+                pos2 -= 1;
+                tree = tree->brother;
+            }
+            else
+            {
+                //否则没了
+                return NULL;
+            }
+        }
+        else if (pos1 == strlen(tree->path) - 1) //如果全部相等,node->path查找完毕,继续判断pos2是不是相等
+        {
+            if (pos2 == strlen(path) - 1) //传入的path也全部扫描完毕,则当前节点就是搜索到的节点
+            {
+                return tree;
+            }
+            else //否则,pos1重置为0,从下一个节点继续查找
+            {
+                pos1 = -1;
+                tree = tree->next;
+            }
+        }
+    }
+
+    return NULL;
+}
+
+int main()
+{
+    tree = newNode();
+    insert(tree, "/user/login", 111);
+    insert(tree, "/user/register", 222);
+    insert(tree, "/user/logout", 333);
+    insert(tree, "/user/message", 444);
+    insert(tree, "/user/mess", 555);
+
+    trieNode tmp = search(tree, "/user/mess");
+}