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int initHashTable(HashTable* table, int bucket_num)
{
   table->bucket_num = bucket_num;
   table->bucket = (HashNode**)malloc(sizeof(HashNode*) * bucket_num);
   if (table->bucket == NULL) {
       printf("Alloc memory failed.\n");
       return -1;
   }
    // 此处一定要做初始化工作，否则可能存在非法内存访问的情况
   memset(table->bucket, 0, sizeof(HashNode*) * bucket_num);
   return 0;
}

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struct ListNode {
    int val;
    struct ListNode *next;
};

ListNode* initNode(int val)
{
    ListNode* node = (ListNode*)malloc(sizeof(ListNode));
    if (node == NULL) {
        return NULL;
    }
    node->val = val;
     // 注意此处一定要初始化，否则有可能访问到非法内存
    node->next = NULL;
}

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//Unless that value is 0 (in which case you can omit some part of the initializer and 
//the corresponding elements will be initialized to 0), there's no easy way.

//Don't overlook the obvious solution, though:
int myArray[10] = { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 };

//Elements with missing values will be initialized to 0:
// initialize to 1,2,0,0,0...
int myArray[10] = { 1, 2 }; 

//So this will initialize all elements to 0:
int myArray[10] = { 0 }; // all elements 0

//In C++, an empty initialization list will also initialize every element to 0. This is not allowed with C:
int myArray[10] = {}; // all elements 0 in C++

//Remember that objects with static storage duration will initialize to 0 if no initializer is specified:
static int myArray[10]; // all elements 0

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//If you don't want to change the strings, then you could simply do
const char *a[2];
a[0] = "blah";
a[1] = "hmm";

//If you do want to be able to change the actual string content, the you have to do something like
char a[2][14];
strcpy(a[0], "blah");
strcpy(a[1], "hmm");

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char str[] = "0x1800785";
int num;

sscanf(str, "%x", &num);
printf("0x%x %i\n", num, num); 

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// typedef existing_name alias_name;
typedef unsigned int UINT;

typedef struct Node {
    int val;
    struct Node* next;
} Node;

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//声明返回指针数组的函数
int (*func(int i))[10]; 
//声明一个指向函数的指针(pf)
bool (*pf)(const string &, const string &); 
//声明一个名字为pf的函数，该函数返回bool*
bool *pf(cosnt string&, const string &);
//声明一个返回函数指针的函数
int (*f1(int))(int *, int);

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int main(){
    int c[4]={1,2,3,4};
    int *a[4]; //指针数组
    int (*b)[4]; //数组指针
    
    b=&c;
    //将数组c中元素赋给数组a
    for(int i=0;i<4;i++){
        a[i]=&c[i];
    }
    
    //输出看下结果
    cout<<*a[1]<<endl; //输出2就对
    cout<<(*b)[2]<<endl; //输出3就对
    return 0;
}

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int data[10];
cout << sizeof(data) << endl;
cout << data << &data << endl;

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char str1[10] = "I Love U";
str1++;			//该语句编译时会出错，因为str1是常量

strcpy(str2, str1);	//标记2
cout << "string array 1: " << str1 << endl;
cout << "string array 2: " << str2 << endl;

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char str1[10] = "I Love U";
char *pStr = str;    //标记1
cout << sizeof(pStr) << endl;

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#include <iostream>
void arrayTest(char str[]){
    cout << sizeof(str) << endl;
}

int main() {
    char str1[10] = "I Love U";
    arrayTest(str1);
    return 0;
}