笔试编程题2

1，统计输入的字符串的各个字母的数目，并按数目的大小输出，并显示所占百分比 

主要是通过线性表的顺序表示和冒泡排序实现

/*********************************************************************************
 *      Copyright:  (C) 2014 zhoutian
 *                  All rights reserved.
 *
 *       Filename:  totalchar.c
 *    Description:  统计输入的字符串的各个字母的数目，并按数目的大小输出，并显示所占百分比 
 *                 
 *        Version:  1.0.0(2014年10月21日)
 *         Author:  zhoutian <zhoutian220@163.com>
 *      ChangeLog:  1, Release initial version on "2014年11月08日 15时16分40秒"
 *                 
 ********************************************************************************/

#include <stdio.h>
#include <stdlib.h>

#define MAX 51                /* 输入的字符的最大值 */
#define    LIST_INIT_SIZE 20        /*静态表存储空间的初始分配量  */

typedef struct  
{
    char alpha;
    int count;
}ElemType;

typedef struct  
{
    ElemType *elem;
    int total;  //输入的总字母数
    int num;     //已使用的结点数
}SqList;

//注意：函数声明放在结构体定义之后
int AddNode(SqList *list, char alpha);
void total(SqList *list, char alpha);
int ListSort(SqList *list);
int ListShow(const SqList *list);

/*  */
int main (int argc, char **argv)
{
    SqList list;
    char str[MAX];
    int i = 0;

    list.num = list.total = 0;
    list.elem = (ElemType *)malloc(LIST_INIT_SIZE*sizeof(ElemType));
    if(list.elem == NULL)
    {
        printf ("malloc error\n");
        return -1;
    }

    printf ("input string(max number is:%d)\n",MAX-1);
    fgets(str,MAX-1,stdin);

    while(str[i] != '\0') 
    {
        if(isalpha(str[i]))
        {
            total(&list, toupper(str[i]));
            list.total ++;
        }
        i++;
    }

    ListShow(&list);
    printf("after sort\n");
    ListSort(&list);
    ListShow(&list);

    return 0;
} /* ----- End of main() ----- */

/* 统计输入的各个字母的个数 */
void total(SqList *list, char alpha)
{
    ElemType *elem = list->elem;
    int num = list->num;
    int i = 0;

    while(i<num  && elem[i].alpha!=alpha) //遍历链表，查看是否有相同的字母
    {
        i++;
    }
    if(elem[i].alpha == alpha) elem[i].count ++; //node不为空且找到等于alpha的字符，则该节点的count++
    else AddNode(list,alpha);
}

/* 使用冒泡排序根据elem[i].count从小到大排序 */
int ListSort(SqList *list)
{
    ElemType *elem = list->elem;
    ElemType temp;
    int num = list->num;
    int i = 0, j = 0;
    int exchange;

    for(i=0; i<num-1; i++)
    {
        exchange = 0;
        for(j=num-2; j>i; j--)
        {
            if(elem[j].count < elem[j+1].count)
            {
                temp = elem[j];
                elem[j] = elem[j+1];
                elem[j+1] = temp;
                exchange = 1;
            }
            if(exchange == 0) return 0;
        }
    }

    return 0;    
}

int ListShow(const SqList *list)
{
    ElemType *elem = list->elem;
    int num = list->num;
    int i;

    for(i=0; i<num; i++)
    {
        printf ("alpha %c: %d  %.2f\n",elem[i].alpha, elem[i].count, (float)elem[i].count/list->total);
    }

    return 0;
}


/* 在静态表的末尾添加一个新的数据 */
int AddNode(SqList *list, char alpha)
{
    ElemType *elem = list->elem;
    int num = list->num;

    elem[num].count = 1;
    elem[num].alpha = alpha;
    list->num ++;

    return 0;
}