統計檔案中各單詞出現的頻率（二叉排序樹實現）

統計檔案中各單詞出現的頻率（二叉排序樹實現）

#include<stdio.h>#include<stdlib.h>#include<string.h>#include<ctype.h>#define MAX 50typedef struct BTNode{char *word;unsigned long count;struct BTNode *lchild;struct BTNode *rchild;}BTNode;void GetWord(FILE *fp,int lim,char word[])//擷取一個單詞{char *w=word;int c;while(isspace(c=getc(fp)))//跳過空格;if(c!=EOF)*word++=c;if(!isalpha(c))//單詞第一個不是字母，退出{*word='\0';return ;}for( ;--lim>0;word++)if(!isalnum(*word=getc(fp)))//不是字母或數字，退出break;*word='\0';word=w;}BTNode *AddTree(BTNode *root,char *w){if(root==NULL){root=(BTNode *)malloc(sizeof(BTNode)*1);if(!root){printf("No enough memory!\n");exit(-1);}else{root->word=(char *)malloc(sizeof(char)*MAX);if(!root->word){printf("No enough memory!\n");    exit(-1);}}strcpy(root->word,w);root->count=1;root->lchild=root->rchild=NULL;}else if(strcmp(w,root->word)==0)root->count++;else if(strcmp(w,root->word)>0)root->rchild=AddTree(root->rchild,w);elseroot->lchild=AddTree(root->lchild,w);return root;}void TreePrint(BTNode *root,FILE *fp){if(root){TreePrint(root->lchild,fp);fprintf(fp,"%4ld %s\n",root->count,root->word);TreePrint(root->rchild,fp);}}void DTree(BTNode *root)//銷毀二叉樹{BTNode *p=root;if(!p)return;DTree(p->lchild);DTree(p->rchild);free(p);p=NULL;}int main(int argc,char *argv[]){BTNode *root=NULL;FILE *fp,*out;char word[MAX];int sumwords=0;fp=fopen("text.txt","r");out=fopen("out.txt","w");if(fp==NULL){printf("Can not open the file!\n");exit(-1);}if(out==NULL){printf("Can not open the file!\n");exit(-1);}while(!feof(fp)){GetWord(fp,MAX,word);if(isalpha(word[0]))//如果Word第一個是字母，則加入到二叉樹中{root=AddTree(root,word);sumwords++;}}TreePrint(root,out);    printf("The all words are: %d\n",sumwords);fclose(fp);fclose(out);DTree(root);return 0;}