HDU 1247-Hat’s Words

港控/mmm° 2022-09-24 06:17 51阅读 0赞

HDU 1247

Description  
A hat’s word is a word in the dictionary that is the concatenation of exactly two other words in the dictionary.  
You are to find all the hat’s words in a dictionary.

Input  
Standard input consists of a number of lowercase words, one per line, in alphabetical order. There will be no more than 50,000 words.  
Only one case.

Output  
Your output should contain all the hat’s words, one per line, in alphabetical order.

Sample Input  
a  
ahat  
hat  
hatword  
hziee  
word

Sample Output  
ahat  
hatword

代码如下：

#include<stdio.h>
    #include<string.h>
    #include<stdlib.h>
    #define N 26
    char s[50005][100];
    struct node {
        struct node *child[N];
        int flag;
    };
    struct node *root;
    void inital(struct node *p) 
    {
        int i;
        for(i=0;i<N;i++) 
        {
            p->child[i]=NULL;
        }
        p->flag=0;
        return;
    }
    void insert(char *str)
    {
        int i,len,k;
        struct node *newnode,*current;
        len=strlen(str);
        current=root;
        if(len==0) return ;
    
        for(i=0;i<len;i++) 
        {
            k=str[i]-'a';
            if(current->child[k]!=NULL)
                current=current->child[k];
            else 
            {
                newnode=(struct node *)malloc(sizeof(struct node));
                inital(newnode);
                current->child[k]=newnode;
                current=newnode;
            }
        }
        current->flag=1;
    }
    
    int find(char *str)
    {
        int len,i,k;
        struct node *current;
        current=root;
        len=strlen(str);
        for(i=0;i<len;i++) 
        {
            k=str[i]-'a';
            if(current->child[k]!=NULL) 
            {
                current=current->child[k];
            }
            else 
                return 0;
        }
        return current->flag;
    }
    
    int main() 
    {
    
        int i,j,ans,n=0,len;
        char s1[100],s2[100];
        root=(struct node *)malloc(sizeof(struct node));
        inital(root);
        while(scanf("%s",s[n])!=EOF)
        { 
            insert(s[n]);
            n++;
        }
        for(i=0;i<n;i++) 
        {
            len=strlen(s[i]);
            for(j=1;j<=len-1;j++) 
            {
                strncpy(s1,s[i],j);
                s1[j]='\0';
                strncpy(s2,s[i]+j,len-j);
                s2[len-j]='\0';
                ans=find(s1)+find(s2);
                if(ans==2)
                {
                    printf("%s\n",s[i]);
                    break;
                }
            }
        }
        return 0;    
    }