Modify the code style of C (#299)

* style(my_list): modify c codes.

* style(stack): modify c codes.

* style(hash): modify c codes.

codes/c/chapter_array_and_linkedlist/my_list.c

@@ -6,57 +6,59 @@
 
 #include "../include/include.h"
 
-
 // 用数组实现 list
-struct mylist {
-    int* nums;       // 数组（存储列表元素）
+struct myList {
+    int *nums;       // 数组（存储列表元素）
     int capacity;    // 列表容量
     int size;        // 列表大小
     int extendRatio; // 列表每次扩容的倍数
 };
 
-typedef struct mylist MyList;
+typedef struct myList myList;
+
 /* 前置声明 */
-void extendCapacity(MyList *list);
+void extendCapacity(myList *list);
 
 /* 构造函数 */
-void newMyList(MyList *list) {
+myList *newMyList() {
+    myList *list = malloc(sizeof(myList));
     list->capacity = 10;
     list->nums = malloc(sizeof(int) * list->capacity);
     list->size = 0;
     list->extendRatio = 2;
+    return list;
 }
 
 /* 析构函数 */
-void delMyList(MyList *list) {
-    list->size = 0;
+void delMyList(myList *list) {
     free(list->nums);
+    free(list);
 }
 
 /* 获取列表长度 */
-int size(MyList *list) {
+int size(myList *list) {
     return list->size;
 }
 
 /* 获取列表容量 */
-int capacity(MyList *list) {
+int capacity(myList *list) {
     return list->capacity;
 }
 
 /* 访问元素 */
-int get(MyList *list, int index) {
+int get(myList *list, int index) {
     assert(index < list->size);
     return list->nums[index];
 }
 
 /* 更新元素 */
-void set(MyList *list, int index, int num) {
+void set(myList *list, int index, int num) {
     assert(index < list->size);
     list->nums[index] = num;
 }
 
 /* 尾部添加元素 */
-void add(MyList *list, int num) {
+void add(myList *list, int num) {
     if (size(list) == capacity(list)) {
         extendCapacity(list); // 扩容
     }
@@ -65,10 +67,10 @@ void add(MyList *list, int num) {
 }
 
 /* 中间插入元素 */
-void insert(MyList *list, int index, int num) {
+void insert(myList *list, int index, int num) {
     assert(index < size(list));
     for (int i = size(list); i > index; --i) {
-      list->nums[i] = list->nums[i-1];
+        list->nums[i] = list->nums[i - 1];
     }
     list->nums[index] = num;
     list->size++;
@@ -77,25 +79,25 @@ void insert(MyList *list, int index, int num) {
 /* 删除元素 */
 // 由于引入了 stdio.h ，此处无法使用 remove 关键词
 // 详见 https://github.com/krahets/hello-algo/pull/244#discussion_r1067863888
-int removeNum(MyList *list, int index) {
+int removeNum(myList *list, int index) {
     assert(index < size(list));
     int num = list->nums[index];
     for (int i = index; i < size(list) - 1; i++) {
-        list->nums[i] = list->nums[i+1];
+        list->nums[i] = list->nums[i + 1];
     }
     list->size--;
     return num;
 }
 
 /* 列表扩容 */
-void extendCapacity(MyList *list) {
+void extendCapacity(myList *list) {
     // 先分配空间
     int newCapacity = capacity(list) * list->extendRatio;
-    int *extend = (int *)malloc(sizeof(int) * newCapacity);
+    int *extend = (int *) malloc(sizeof(int) * newCapacity);
     int *temp = list->nums;
 
     // 拷贝旧数据到新数据
-    for(int i = 0; i < size(list); i++)
+    for (int i = 0; i < size(list); i++)
         extend[i] = list->nums[i];
 
     // 释放旧数据
@@ -107,53 +109,52 @@ void extendCapacity(MyList *list) {
 }
 
 /* 将列表转换为 Array 用于打印 */
-int* toArray(MyList *list) {
+int *toArray(myList *list) {
     return list->nums;
 }
 
 int main() {
     /* 初始化列表 */
-    MyList list;
-    newMyList(&list);
+    myList *list = newMyList();
     /* 尾部添加元素 */
-    add(&list, 1);
-    add(&list, 3);
-    add(&list, 2);
-    add(&list, 5);
-    add(&list, 4);
+    add(list, 1);
+    add(list, 3);
+    add(list, 2);
+    add(list, 5);
+    add(list, 4);
     printf("列表 list = ");
-    printArray(toArray(&list), size(&list));
-    printf("容量 = %d ，长度 = %d\r\n", capacity(&list), size(&list));
+    printArray(toArray(list), size(list));
+    printf("容量 = %d ，长度 = %d\n", capacity(list), size(list));
 
     /* 中间插入元素 */
-    insert(&list, 3, 6);
+    insert(list, 3, 6);
     printf("在索引 3 处插入数字 6 ，得到 list = ");
-    printArray(toArray(&list), size(&list));
+    printArray(toArray(list), size(list));
 
     /* 删除元素 */
-    removeNum(&list, 3);
+    removeNum(list, 3);
     printf("删除索引 3 处的元素，得到 list = ");
-    printArray(toArray(&list), size(&list));  
+    printArray(toArray(list), size(list));
 
     /* 访问元素 */
-    int num = get(&list, 1);
-    printf("访问索引 1 处的元素，得到 num = %d\r\n", num);
+    int num = get(list, 1);
+    printf("访问索引 1 处的元素，得到 num = %d\n", num);
 
     /* 更新元素 */
-    set(&list, 1, 0);
+    set(list, 1, 0);
     printf("将索引 1 处的元素更新为 0 ，得到 list = ");
-    printArray(toArray(&list), size(&list));
+    printArray(toArray(list), size(list));
 
     /* 测试扩容机制 */
     for (int i = 0; i < 10; i++) {
         // 在 i = 5 时，列表长度将超出列表容量，此时触发扩容机制
-        add(&list, i);
+        add(list, i);
     }
 
     printf("扩容后的列表 list = ");
-    printArray(toArray(&list), size(&list));
-    printf("容量 = %d ，长度 = %d\r\n", capacity(&list), size(&list));
+    printArray(toArray(list), size(list));
+    printf("容量 = %d ，长度 = %d\n", capacity(list), size(list));
 
-    /* 析构函数，释放分配内存 */
-    delMyList(&list);
+    /* 释放分配内存 */
+    delMyList(list);
 }

codes/c/chapter_computational_complexity/CMakeLists.txt

@@ -1,2 +1,3 @@
 add_executable(time_complexity time_complexity.c )
-add_executable(worst_best_time_complexity worst_best_time_complexity.c)
+add_executable(worst_best_time_complexity worst_best_time_complexity.c)
+add_executable(leetcode_two_sum leetcode_two_sum.c)

codes/c/chapter_computational_complexity/leetcode_two_sum.c

@@ -0,0 +1,85 @@
+/**
+ * File: leetcode_two_sum.c
+ * Created Time: 2023-01-19
+ * Author: Reanon (793584285@qq.com)
+ */
+
+#include "../include/include.h"
+
+/* 暴力解法 */
+int *twoSumBruteForce(int *nums, int numsSize, int target, int *returnSize) {
+    for (int i = 0; i < numsSize; ++i) {
+        for (int j = i + 1; j < numsSize; ++j) {
+            if (nums[i] + nums[j] == target) {
+                int *ret = malloc(sizeof(int) * 2);
+                ret[0] = i, ret[1] = j;
+                *returnSize = 2;
+                return ret;
+            }
+        }
+    }
+    *returnSize = 0;
+    return NULL;
+}
+
+/* 哈希表 */
+struct hashTable {
+    int key;
+    int val;
+    // 借助 LetCode 上常用的哈希表
+    UT_hash_handle hh;
+};
+
+typedef struct hashTable hashTable;
+
+hashTable *find(hashTable *h, int key) {
+    hashTable *tmp;
+    HASH_FIND_INT(h, &key, tmp);
+    return tmp;
+}
+
+void insert(hashTable *h, int key, int val) {
+    hashTable *t = find(h, key);
+    if (t == NULL) {
+        hashTable *tmp = malloc(sizeof(hashTable));
+        tmp->key = key, tmp->val = val;
+        HASH_ADD_INT(h, key, tmp);
+    } else {
+        t->val = val;
+    }
+}
+
+
+int *twoSumHashTable(int *nums, int numsSize, int target, int *returnSize) {
+    hashTable *hashtable = NULL;
+    for (int i = 0; i < numsSize; i++) {
+        hashTable *t = find(hashtable, target - nums[i]);
+        if (t != NULL) {
+            int *ret = malloc(sizeof(int) * 2);
+            ret[0] = t->val, ret[1] = i;
+            *returnSize = 2;
+            return ret;
+        }
+        insert(hashtable, nums[i], i);
+    }
+    *returnSize = 0;
+    return NULL;
+}
+
+int main() {
+    // ======= Test Case =======
+    int nums[] = {2, 7, 11, 15};
+    int target = 9;
+    // ====== Driver Code ======
+    int returnSize;
+    int *res = twoSumBruteForce(nums, sizeof(nums) / sizeof(int), target, &returnSize);
+    // 方法一
+    printf("方法一 res = ");
+    printArray(res, returnSize);
+
+    // 方法二
+    res = twoSumHashTable(nums, sizeof(nums) / sizeof(int), target, &returnSize);
+    printf("方法二 res = ");
+    printArray(res, returnSize);
+    return 0;
+}

codes/c/chapter_sorting/quick_sort.c

@@ -63,7 +63,7 @@ int medianThree(int nums[], int left, int mid, int right) {
 }
 
 // 哨兵划分（三数取中值）
-int QuickSortMedianPartition(int nums[], int left, int right) {
+int quickSortMedianPartition(int nums[], int left, int right) {
     // 选取三个候选元素的中位数
     int med = medianThree(nums, left, (left + right) / 2, right);
     // 将中位数交换至数组最左端
@@ -87,7 +87,7 @@ void quickSortMedian(int nums[], int left, int right) {
     if (left >= right)
         return;
     // 哨兵划分
-    int pivot = QuickSortMedianPartition(nums, left, right);
+    int pivot = quickSortMedianPartition(nums, left, right);
     // 递归左子数组、右子数组
     quickSortMedian(nums, left, pivot - 1);
     quickSortMedian(nums, pivot + 1, right);

codes/c/chapter_stack_and_queue/array_stack.c

@@ -6,118 +6,98 @@
 
 #include "../include/include.h"
 
+#define MAX_SIZE 5000
+
 /* 基于数组实现的栈 */
-struct ArrayStack {
-    int *stackTop;
+struct arrayStack {
+    int *data;
     int size;
-    int capacity;
 };
 
-typedef struct ArrayStack ArrayStack;
+typedef struct arrayStack arrayStack;
 
-/* 内部调用 */
-/* 获取栈容量 */
-static int capacity(ArrayStack *stk) {
-    return stk->capacity;
-}
-
-/* 栈自动扩容 */
-static void extendCapacity(ArrayStack *stk) {
-    // 先分配空间
-    int newCapacity = capacity(stk) * 2;
-    int *extend = (int *)malloc(sizeof(int) * newCapacity);
-    int *temp = stk->stackTop;
-
-    // 拷贝旧数据到新数据
-    for(int i=0; i<stk->size; i++)
-        extend[i] = temp[i];
-
-    // 释放旧数据
-    free(temp);
-
-    // 更新新数据
-    stk->stackTop = extend;
-    stk->capacity = newCapacity;
-}
-
-/* 构造函数 */
-void newArrayStack(ArrayStack *stk) {
-    stk->capacity = 10;
-    stk->size = 0;
-    stk->stackTop = (int *)malloc(sizeof(int) * stk->capacity);
-}
-
-/* 析构函数 */
-void delArrayStack(ArrayStack *stk) {
-    stk->capacity = 0;
-    stk->size = 0;
-    free(stk->stackTop);
+arrayStack *newArrayStack() {
+    arrayStack *s = malloc(sizeof(arrayStack));
+    // 初始化一个大容量，避免扩容
+    s->data = malloc(sizeof(int) * MAX_SIZE);
+    s->size = 0;
+    return s;
 }
 
 /* 获取栈的长度 */
-int size(ArrayStack *stk) {
-    return stk->size;
+int size(arrayStack *s) {
+    return s->size;
 }
 
 /* 判断栈是否为空 */
-bool empty(ArrayStack *stk) {
-    return size(stk) == 0;
-}
-
-/* 访问栈顶元素 */
-int top(ArrayStack *stk) {
-    return stk->stackTop[size(stk) - 1];
+bool isEmpty(arrayStack *s) {
+    return s->size == 0;
 }
 
 /* 入栈 */
-void push(ArrayStack *stk, int num) {
-    if (size(stk) == capacity(stk)) 
-        extendCapacity(stk);        // 需要扩容
+void push(arrayStack *s, int num) {
+    if (s->size == MAX_SIZE) {
+        printf("stack is full.\n");
+        return;
+    }
+    s->data[s->size] = num;
+    s->size++;
+}
 
-    stk->stackTop[size(stk)] = num;
-    stk->size++;
+/* 访问栈顶元素 */
+int peek(arrayStack *s) {
+    if (s->size == 0) {
+        printf("stack is empty.\n");
+        return NIL;
+    }
+    return s->data[s->size - 1];
 }
 
 /* 出栈 */
-void pop(ArrayStack *stk) {
-    int num = stk->stackTop[size(stk) - 1];
-    stk->size--;
+int pop(arrayStack *s) {
+    if (s->size == 0) {
+        printf("stack is empty.\n");
+        return NIL;
+    }
+    int val = peek(s);
+    s->size--;
+    return val;
 }
 
 /* Driver Code */
 int main() {
     /* 初始化栈 */
-    ArrayStack stack;
-    newArrayStack(&stack);
+    arrayStack * stack = newArrayStack();
 
     /* 元素入栈 */
-    push(&stack, 1);
-    push(&stack, 3);
-    push(&stack, 2);
-    push(&stack, 5);
-    push(&stack, 4);
-
+    push(stack, 1);
+    push(stack, 3);
+    push(stack, 2);
+    push(stack, 5);
+    push(stack, 4);
     printf("栈 stack = ");
-    printArray(stack.stackTop, size(&stack));
+    printArray(stack->data, stack->size);
 
     /* 访问栈顶元素 */
-    int stackTop = top(&stack);
-    printf("栈顶元素 top = %d\r\n", stackTop);
+    int val = peek(stack);
+    printf("栈顶元素 top = %d\n", val);
 
     /* 元素出栈 */
-    pop(&stack);
-    printf("出栈元素 pop = %d, 出栈后 stack =  ", stackTop);
-    printArray(stack.stackTop, size(&stack));
+    val = pop(stack);
+    printf("出栈元素 pop = %d，出栈后 stack = ", val);
+    printArray(stack->data, stack->size);
 
     /* 获取栈的长度 */
-    int stackSize = size(&stack);
-    printf("栈的长度 size = %d\r\n", stackSize);
+    int size = stack->size;
+    printf("栈的长度 size =  %d\n", size);
 
     /* 判断是否为空 */
-    bool isEmpty = empty(&stack);
-    printf("栈是否为空 = %s\r\n", isEmpty ? "yes" : "no");
+    bool empty = isEmpty(stack);
+    printf("栈是否为空 = %s\n", empty ? "true" : "false");
+
+    // 释放内存
+    free(stack->data);
+    free(stack);
 
-    /* 析构函数 */
-    delArrayStack(&stack);
     return 0;
 }

codes/c/chapter_stack_and_queue/linkedlist_stack.c

@@ -7,104 +7,109 @@
 #include "../include/include.h"
 
 /* 基于链表实现的栈 */
-struct LinkedListStack {
-    ListNode* stackTop; // 将头结点作为栈顶
+struct linkedListStack {
+    ListNode *top; // 将头结点作为栈顶
     int size;           // 栈的长度
 };
 
-typedef struct LinkedListStack LinkedListStack;
+typedef struct linkedListStack linkedListStack;
 
 /* 构造函数 */
-void newLinkedListStack(LinkedListStack* stk) {
-    stk->stackTop = NULL;
-    stk->size = 0;
+linkedListStack *newLinkedListStack() {
+    linkedListStack *s = malloc(sizeof(linkedListStack));
+    s->top = NULL;
+    s->size = 0;
+    return s;
 }
 
 /* 析构函数 */
-void delLinkedListStack(LinkedListStack* stk) {
-    while(stk->stackTop) {
-        ListNode *n = stk->stackTop->next;
-        free(stk->stackTop);
-        stk->stackTop = n;
+void delLinkedListStack(linkedListStack *s) {
+    while (s->top) {
+        ListNode *n = s->top->next;
+        free(s->top);
+        s->top = n;
     }
-    stk->size = 0;
+    free(s);
 }
 
 /* 获取栈的长度 */
-int size(LinkedListStack* stk) {
-    assert(stk);
-    return stk->size;
+int size(linkedListStack *s) {
+    assert(s);
+    return s->size;
 }
 
 /* 判断栈是否为空 */
-bool empty(LinkedListStack* stk) {
-    assert(stk);
-    return size(stk) == 0;
+bool isEmpty(linkedListStack *s) {
+    assert(s);
+    return size(s) == 0;
 }
 
 /* 访问栈顶元素 */
-int top(LinkedListStack* stk) {
-    assert(stk);
-    assert(size(stk) != 0); 
-    return stk->stackTop->val;
+int peek(linkedListStack *s) {
+    assert(s);
+    assert(size(s) != 0);
+    return s->top->val;
 }
 
 /* 入栈 */
-void push(LinkedListStack* stk, int num) {
-    assert(stk);
-    ListNode *node = (ListNode *)malloc(sizeof(ListNode));
-    node->next = stk->stackTop; // 更新新加结点指针域
-    node->val = num;            // 更新新加结点数据域
-    stk->stackTop = node;       // 更新栈顶
-    stk->size++;             // 更新栈大小
+void push(linkedListStack *s, int num) {
+    assert(s);
+    ListNode *node = (ListNode *) malloc(sizeof(ListNode));
+    node->next = s->top;   // 更新新加结点指针域
+    node->val = num;       // 更新新加结点数据域
+    s->top = node;         // 更新栈顶
+    s->size++;             // 更新栈大小
 }
 
 /* 出栈 */
-void pop(LinkedListStack* stk) {
-    assert(stk);
-    int num = top(stk);
-    ListNode *tmp = stk->stackTop;
-    stk->stackTop = stk->stackTop->next;
+int pop(linkedListStack *s) {
+    if (s->size == 0) {
+        printf("stack is empty.\n");
+        return NIL;
+    }
+    assert(s);
+    int val = peek(s);
+    ListNode *tmp = s->top;
+    s->top = s->top->next;
     // 释放内存
     free(tmp);
-    stk->size--;
+    s->size--;
+    return val;
 }
 
 /* Driver Code */
 int main() {
     /* 初始化栈 */
-    LinkedListStack stack;
-    /* 构造函数 */
-    newLinkedListStack(&stack);
+    // 构造函数
+    linkedListStack *stack = newLinkedListStack();
 
     /* 元素入栈 */
-    push(&stack, 1);
-    push(&stack, 3);
-    push(&stack, 2);
-    push(&stack, 5);
-    push(&stack, 4);
+    push(stack, 1);
+    push(stack, 3);
+    push(stack, 2);
+    push(stack, 5);
+    push(stack, 4);
 
     printf("栈 stack = ");
-    printLinkedList(stack.stackTop);
+    printLinkedList(stack->top);
 
     /* 访问栈顶元素 */
-    int stackTop = top(&stack);
-    printf("栈顶元素 top = %d\r\n", stackTop);
+    int val = peek(stack);
+    printf("栈顶元素 top = %d\r\n", val);
 
     /* 元素出栈 */
-    pop(&stack);
-    printf("出栈元素 pop = %d, 出栈后 stack =  ", stackTop);
-    printLinkedList(stack.stackTop);
+    val = pop(stack);
+    printf("出栈元素 pop = %d, 出栈后 stack =  ", val);
+    printLinkedList(stack->top);
 
     /* 获取栈的长度 */
-    int stackSize = size(&stack);
-    printf("栈的长度 size = %d\r\n", stackSize);
+    printf("栈的长度 size = %d\n", size(stack));
 
     /* 判断是否为空 */
-    bool isEmpty = empty(&stack);
-    printf("栈是否为空 = %s\r\n", isEmpty ? "yes" : "no");
+    bool empty = isEmpty(stack);
+    printf("栈是否为空 = %s\n", empty ? "true" : "false");
 
     /* 析构函数 */
-    delLinkedListStack(&stack);
+    delLinkedListStack(stack);
     return 0;
 }

codes/c/include/CMakeLists.txt

@@ -1,4 +1,5 @@
 add_executable(include
         include_test.c
+        uthash.h
         include.h print_util.h
         list_node.h tree_node.h)

codes/c/include/include.h

@@ -14,6 +14,8 @@
 #include <time.h>
 #include <assert.h>
 
+#include "uthash.h"
+
 #include "list_node.h"
 #include "tree_node.h"
 #include "print_util.h"