C语言实现英文文本词频统计

//
// main.c
// word_frequency_statistic
//
// Created by tianling on 14-3-16.
// Copyright (c) 2014年 tianling. All rights reserved.
// 实现英文文本的词频统计
//

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

#define ERROR 1
#define OK 0
const int WORD_LENGTH = 250;//定义单个单词最大长度
typedef int status;


/*
 **定义存储单词及其出现次数的结构体
 */
typedef struct Node{
 char word[WORD_LENGTH];
 int time;
 struct Node *next;
}wordNode;

wordNode *headNode = NULL;//定义链表头指针

/*
 **函数声明
 */
wordNode *wordSearch(char *word,int *num);
status wordCount(char *word,int *num);
void printCountList(int *num);
void PrintFirstTenTimes();
void mergeSort(wordNode **head);
void FrontBackSplit(wordNode *head,wordNode **pre,wordNode **next);
void wordJob(char word[]);
wordNode *SortedMerge(wordNode *pre,wordNode *next);
void release();

status main(int argc,char *argv[])
{
 char temp[WORD_LENGTH];//定义用以临时存放单词的数组
 FILE *file;
 int count,articleWordNum = 0;//定义统计结点个数的变量
 int *num = &articleWordNum,choose;
 
 /*
  **读取文件
  */
 if((file = fopen("/Users/tianling/Documents/Data_Structure/word_frequency_statistic/word_frequency_statistic/article.txt", "r")) == NULL){
  //这里是绝对路径，基于XCode编译器查找方便的需求
  printf("文件读取失败!");
  exit(1);
 }
 
 while((fscanf(file,"%s",temp))!= EOF){
  wordJob(temp);
  count = wordCount(temp,num);
 }
 
 fclose(file);//关闭文件
 
 printCountList(num);
 
 printf("***********请选择***********\n");
 printf("*****1. 输出词频最高的10个词**\n");
 printf("*****2. 退出****************\n");
 
 scanf("%d",&choose);
 if(choose == 1){
  mergeSort(&headNode);
  PrintFirstTenTimes();

 }else{
  release();
  exit(0);
 }
 
 release();
 return 0;
 
 
}

/*
 **查找单词所在结点
 */
wordNode *wordSearch(char *word,int *num){
 wordNode *node;//声明一个新结点
 
 if(headNode == NULL){//若头结点为空
  node = (wordNode*)malloc(sizeof(wordNode));
  strcpy(node->word, word);//将第一个单词赋值给这个新结点
  node->time = 0;//初始化该单词的出现次数
  *num+=1;
  headNode = node;//将头结点指向这个新结点
  return node;
  
 }
 
 wordNode *nextNode = headNode;
 wordNode *preNode = NULL;
 
 while(nextNode != NULL && strcmp(nextNode->word, word) != 0){
  preNode = nextNode;
  nextNode = nextNode->next;
 }
 
 //若该单词不存在，则在链表中生成新结点
 if(nextNode == NULL){
  node = (wordNode*)malloc(sizeof(wordNode));
  strcpy(node->word, word);
  node->time = 0;
  node->next = headNode->next;
  headNode->next = node;
  *num+=1;
  
  return node;
 }else
  return nextNode;
 
}


/*
 **词频统计
 */
status wordCount(char *word,int *num){
 wordNode *tmpNode = NULL;
 tmpNode = wordSearch(word,num);
 
 if(tmpNode == NULL){
  return ERROR;
 }
 
 tmpNode->time++;
 
 return 0;
}


/*
 **打印所有词频
 */
void printCountList(int *num){
 if(headNode == NULL){
  printf("该文件无内容！");
  
 }else{
  wordNode *preNode = headNode;
  printf("总词量 %d \n",*num);
  
  while(preNode != NULL){
   printf("%s 出现次数 %d\n",preNode->word,preNode->time);
   preNode = preNode->next;
  }
 }
 
}


/*
 **打印词频最高的10个词
 */
void PrintFirstTenTimes(){
 if(headNode == NULL){
  printf("该文件无内容!");
  
 }else{
  wordNode *preNode = headNode;
  int i = 0;
  printf("出现次数最多的10个词如下: \n");
  
  while (preNode != NULL && i<=10) {
   printf("%s 出现次数 %d\n",preNode->word,preNode->time);
   preNode = preNode->next;
   i++;

  }
 }
}


/*
 **对词频统计结果进行归并排序
 */
void mergeSort(wordNode **headnode){
 wordNode *pre,*next,*head;
 head = *headnode;
 
 //若链表长度为0或1则停止排序
 if(head == NULL || head->next == NULL){
  return;
 }
 
 FrontBackSplit(head,&pre,&next);
 
 mergeSort(&pre);
 mergeSort(&next);
 
 *headnode = SortedMerge(pre,next);
 
}


/*
 **将链表进行分组
 */
void FrontBackSplit(wordNode *source,wordNode **pre,wordNode **next){
 wordNode *fast;
 wordNode *slow;
 
 if(source == NULL || source->next == NULL){
  *pre = source;
  *next = NULL;
 }else{
  slow = source;
  fast = source->next;
  
  while(fast != NULL){
   fast = fast->next;
   
   if(fast != NULL){
    slow = slow->next;
    fast = fast->next;
   }
  }
  *pre = source;
  *next = slow->next;
  slow->next = NULL;
 }
}


/*
 **根据排序结果更换头结点
 */
wordNode *SortedMerge(wordNode *pre,wordNode *next){
 wordNode *result = NULL;
 
 if(pre == NULL)
  return next;
 else if(next == NULL)
  return pre;
 
 if(pre->time >= next->time){
  result = pre;
  result->next = SortedMerge(pre->next,next);
  
 }else{
  result = next;
  result->next = SortedMerge(pre,next->next);
 }
 return result;
}


/*
 **处理大写字母及特殊字符
 */
void wordJob(char word[]){
 int i,k;
 char *specialChar = ",.;:'?!><+=|*&^%$#@\"";//定义特殊字符集
 
 for(i = 0;i<strlen(word);i++){
  //筛选并将字符串中的大写字母转化为小写字母
  if(word[i]>='A'&& word[i]<='Z'){
   word[i] += 32;
  }
  //筛选并去除字符串中的特殊字符
  for(k = 0;k<strlen(specialChar);k++){
   
   if(word[i] == specialChar[k]){
    
    while(i<strlen(word)){
     word[i] = word[i+1];
     i++;
    }
    
   }
  }
 }
 
}


/*
 **释放所有结点内存
 */
void release(){
 if(headNode == NULL)
  return;
 
 wordNode *pre = headNode;
 while(pre != NULL){
  headNode = pre->next;
  free(pre);
  pre = headNode;
  
 }
}