数据结构实验：哈希表

think:
1哈希表的建立需要注意映射关系的合理选择，自己开始时候将线性映射关系选择为10000，然后提交就一直超时，而且自己犯得错误很多，题目中说了如果有多个结果，输出数字最小的那个，自己昨晚没有注意，提交wrong answer，今天注意到之后又因为知识掌握不扎实，先是超时错误，又因为盲目修改数组大小，导致数组越界，其实哈希表的建立就像是一种大集合中小集合的模块化，结构体链表数组的很好使用，自己还有就是考虑如果是多组输入，那么如何将结构体数组指针初始化，一直还没想到解决方法，刚刚问了问鑫哥，可以重新用一个for循环将指针数组中的每个指针置空，或者用一个for循环重新为指针数组中的每个指针申请新的空间

数据结构实验：哈希表
Time Limit: 1000MS Memory Limit: 65536KB

Problem Description
在n个数中，找出出现次数最多那个数字，并且输出出现的次数。如果有多个结果，输出数字最小的那一个。

Input
单组数据，第一行数字n（1<=n<=100000)。
接下来有n个数字，每个数字不超过100000000

Output
出现次数最多的数字和次数。

Example Input
3
1 1 2

Example Output
1 2

Hint

Author
cz

以下为accepted代码

#include 
#include 
#define N 100
long long book[100004];
struct node
{
    int Data;
    struct node *next;
};
struct node *a[1000004];

void Inserst(long long n)
{
    long long x = n/N;
    struct node *p = (struct node *)malloc(sizeof(struct node));
    p->Data = n;
    p->next = a[x];
    a[x] = p;
}

int  Find(long long n)
{
    int cnt = 0;
    long long x = n/N;
    if(a[x] != NULL)
    {
        struct node *p;
        p = a[x];
        while(p != NULL)
        {
            if(p->Data == n)
                cnt++;
            p = p->next;
        }
    }
    return cnt;
}

int main()
{
    int n, i, x, max = -199859;
    scanf("%d", &n);
    {
        max = -199859;
        for(i = 0; i < n; i++)
        {
            scanf("%lld", &book[i]);
            Inserst(book[i]);
        }
        for(i = 0; i < n; i++)
        {
            if(Find(book[i]) > max || (Find(book[i]) == max && book[i] < x))
            {
                max = Find(book[i]);
                x = book[i];
            }
        }
        printf("%d %d\n", x, max);
    }
    return 0;
}


/***************************************************
User name: 
Result: Accepted
Take time: 64ms
Take Memory: 9432KB
Submit time: 2017-02-22 18:51:47
****************************************************/

以下为time limit exceeded代码——映射关系过大

#include 
#include 
#define N 100000
long long book[100004];
struct node
{
    int Data;
    struct node *next;
};
struct node *a[100004];

void Inserst(long long n)
{
    long long x = n/N;
    struct node *p = (struct node *)malloc(sizeof(struct node));
    p->Data = n;
    p->next = a[x];
    a[x] = p;
}

int  Find(long long n)
{
    int cnt = 0;
    long long x = n/N;
    if(a[x] != NULL)
    {
        struct node *p;
        p = a[x];
        while(p != NULL)
        {
            if(p->Data == n)
                cnt++;
            p = p->next;
        }
    }
    return cnt;
}

int main()
{
    int n, i, x, max = -199859;
    scanf("%d", &n);
    {
        max = -199859;
        for(i = 0; i < n; i++)
        {
            scanf("%lld", &book[i]);
            Inserst(book[i]);
        }
        for(i = 0; i < n; i++)
        {
            if(Find(book[i]) > max || (Find(book[i]) == max && book[i] < x))
            {
                max = Find(book[i]);
                x = book[i];
            }
        }
        printf("%d %d\n", x, max);
    }
    return 0;
}


/***************************************************
User name: 
Result: Time Limit Exceeded
Take time: 1010ms
Take Memory: 0KB
Submit time: 2017-02-22 17:54:30
****************************************************/

以下为runtime error代码——输入数据记录数组过小（而且映射关系太大，即使数组不越界，也会超时）

#include 
#include 
#define N 10000
long long book[10004];
struct node
{
    int Data;
    struct node *next;
};
struct node *a[10004];

void Inserst(struct node *a[], long long n)
{
    long long x = n/N;
    struct node *p = (struct node *)malloc(sizeof(struct node));
    p->Data = n;
    p->next = a[x];
    a[x] = p;
}

int  Find(struct node *a[], long long n)
{
    int cnt = 0;
    long long x = n/N;
    if(a[x] != NULL)
    {
        struct node *p;
        p = a[x];
        while(p != NULL)
        {
            if(p->Data == n)
                cnt++;
            p = p->next;
        }
    }
    return cnt;
}

int main()
{
    int n, i, x, max = -199859;
    scanf("%d", &n);
    {
        struct node *a[100004];
        max = -199859;
        for(i = 0; i < n; i++)
        {
            scanf("%lld", &book[i]);
            Inserst(a, book[i]);
        }
        for(i = 0; i < n; i++)
        {
            if(Find(a, book[i]) > max || (Find(a, book[i]) == max && book[i] < x))
            {
                max = Find(a, book[i]);
                x = book[i];
            }
        }
        printf("%d %d\n", x, max);
    }
    return 0;
}


/***************************************************
User name: 
Result: Runtime Error
Take time: 0ms
Take Memory: 0KB
Submit time: 2017-02-22 17:52:37
****************************************************/