单词计数

  1 #include<stdio.h>
  2 #include<ctype.h>
  3 #include<string.h>
  4 #include<stdlib.h>
  5 
  6 #define MAXWORD 100
  7 
  8 struct tnode{
  9     char *word;
 10     int count;
 11     struct tnode *left;
 12     struct tnode *right;
 13 };
 14 
 15 struct tnode *addtree(struct tnode* ,char *);
 16 void treeprint(struct tnode*);
 17 int getword(char *,int);
 18 
 19 main()
 20 {
 21     struct tnode *root;
 22     char word[MAXWORD];
 23     
 24     root=NULL;
 25     while(getword(word,MAXWORD)!=EOF)
 26         if(isalpha(word[0]))
 27             root=addtree(root,word);
 28     
 29     treeprint(root);
 30     
 31     printf("%d\n",num);
 32     
 33     getchar();
 34     int m;
 35     return 0;
 36 }
 37 
 38 struct tnode *talloc()
 39 {
 40     return (struct tnode *) malloc (sizeof(struct tnode));
 41 }
 42  
 43 struct tnode* addtree(struct tnode *p,char *w)
 44 {
 45     int cond;
 46     
 47     if(p==NULL)
 48     {
 49         p=talloc();
 50         p->word=strdup(w);
 51         p->count=1;
 52         p->left=p->right=NULL;
 53     }
 54     else if((cond=strcmp(w,p->word))==0)
 55         p->count++;
 56     else if(cond<0)
 57         p->left=addtree(p->left,w);
 58     else
 59         p->right=addtree(p->right,w);
 60         
 61     return p;
 62 }
 63 
 64 void treeprint(struct tnode *p)
 65 {
 66     if(p!=NULL)
 67     {
 68         treeprint(p->left);
 69         printf("%s %4d\n",p->count,p->word);
 70         //num++;
 71         treeprint(p->right);
 72     }
 73         
 74 }
 75 
 76 
 77 #define BUFFSIZE 100
 78 
 79     char buf[BUFFSIZE];
 80     int bufp=0;
 81 int getch()
 82 {
 83     return bufp>0 ? buf[--bufp] : getchar();
 84 }
 85 
 86 void ungetch(int c)
 87 {
 88     if(bufp>BUFFSIZE)
 89         printf("ungetch: too many characters\n");
 90     else
 91         buf[bufp++]=c;
 92 }
 93 
 94 int getword(char *word,int lim)
 95 {
 96     int c;
 97     char *w=word;
 98     while(isspace(c = getch()))
 99         ;
100     if(c!=EOF)
101         *w++=c;
102     if(!isalpha(c))
103     {
104         *w=‘\0‘;
105         return c;
106     }
107     for(;--lim>0;w++)
108         if(!isalnum(*w=getch()))
109         {
110             ungetch(*w);
111             break;
112         }
113     *w=‘\0‘;
114     return word[0];
115 }